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Effect of Carbon Dioxide (CO_2) Controlled Atmosphere on Superoxide Dismutase (SOD) Activity of Three Storage Pests in Chinese Medicinal Materials 被引量:2
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作者 李灿 《Plant Diseases and Pests》 CAS 2011年第4期43-45,共3页
[ Objective ] The paper was to study the effect of controlled atmosphere stress of carbon dioxide ( CO2 ) on Superoxide dismutase (SOD) activity of in- sect, so as to analyze the biological mechanism of the action... [ Objective ] The paper was to study the effect of controlled atmosphere stress of carbon dioxide ( CO2 ) on Superoxide dismutase (SOD) activity of in- sect, so as to analyze the biological mechanism of the action of controlled atmosphere stress on insect. [ Method] Using nitrotetrazolium blue chloride (NBT) light reduction method, SOD activity of drugstore beetle ( Stegobium panlceum ), cigarette beetle ( Lasioderma serricorne) and coffee bean beetle (Araecerus fasciculatus) was studied, and the stress response of the enzyme under controlled atmosphere stress of CO2 was analyzed. [ Result ] SOD activity of drugstore beetle, cigarette beetle and coffee bean beetle exposed to controlled atmosphere stress of high concentrations of CO2 for 3 and 6 h had certain degree of increase, and the activity sig- nificantly increased from 2.011±0.954,2.664±0.218 and 1.458±0.718 to 3. 135±0. 105,3.050±0.673 and 2.975±0.229 U/(per pest · 30 min) after treat- ment for 6 h. [ Conclusion] Controlled atmosphere stress of high concentrations of CO2 had certain activation effect on SOD activity of storage pest in Chinese me- dicinal material within the context of sub-lethal events. The results could enrich the insecticidal mechanism of controlled atmosphere and theoretical system of analy- sis on insect resistance to controlled atmosphere. 展开更多
关键词 Chinese medicinal materials Storage pest Superoxide dismulase Enzyme activity co2 controlled atmosphere China
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Study of the reaction mechanism for preparing powdered activated coke with SO_(2)adsorption capability via one-step rapid activation method under flue gas atmosphere
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作者 Binxuan Zhou Jingcai Chang +5 位作者 Jun Li Jinglan Hong Tao Wang Liqiang Zhang Ping Zhou Chunyuan Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期158-168,共11页
In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction m... In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction mechanism is summarized.Results indicate that the reaction process of this method can be divided into three stages:stage I is the rapid release of volatiles and the rapid consumption of O_(2),primarily occurring within a reaction time range of 0-0.5 s;stage II is mainly the continuous release and diffusion of volatiles,which is the carbonization and activation coupling reaction stage,and the carbonization process is the main in this stage.This stage mainly occurs at the reaction time range of 0.5 -2.0 s when SL-coal is used as material,and that is 0.5-3.0 s when JJ-coal is used as material;stage III is mainly the activation stage,during which activated components diffuse to both the surface and interior of particles.This stage mainly involves the reaction stage of CO_(2)and H2O(g)activation,and it mainly occurs at the reaction time range of 2.0-4.0 s when SL-coal is used as material,and that is 3.0-4.0 s when JJ-coal is used as material.Besides,the main function of the first two stages is to provide more diffusion channels and contact surfaces/activation sites for the diffusion and activation of the activated components in the third stage.Mastering the reaction mechanism would serve as a crucial reference and foundation for designing the structure,size of the reactor,and optimal positioning of the activator nozzle in PAC preparation. 展开更多
关键词 Reaction mechanism Powdered activated coke preparation SO_(2)adsorption One-step rapid activation Flue gas atmosphere
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Effect of sintering atmosphere on corrosion resistance of Ni/(NiFe_2O_4-10NiO) cermet inert anode for aluminum electrolysis 被引量:3
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作者 田忠良 郭伟昌 +2 位作者 赖延清 张凯 李劼 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第11期2925-2929,共5页
A comparative study on the corrosion resistance of 17Ni/(NiFe2O4-10NiO) cermet inert anode prepared in differentsintering atmospheres was conducted in Na3AlF6-Al2O3 melt. The results indicate that the corrosion rate... A comparative study on the corrosion resistance of 17Ni/(NiFe2O4-10NiO) cermet inert anode prepared in differentsintering atmospheres was conducted in Na3AlF6-Al2O3 melt. The results indicate that the corrosion rates of NiFe2O4-based cermetanodes prepared in the vacuum and the atmosphere with oxygen content of 2×10^-3 (volume fraction) are 6.46 and 2.71 cm/a,respectively. Though there is a transition layer with lots of holes or pores, a densified layer is formed on the surface of anode due tosome reactions producing aluminates. For the anode prepared in the atmosphere with oxygen content of 2×10^-3, the thickness of thedensification layer (about 50 μm) is thicker than that (about 30 μm) formed on the surface of anode prepared in the vacuum. Thecontents of NiO and Fe(II) in NiFe2xO4-y-z increase with the decrease of oxygen content in sintering atmosphere, which reduces thecorrosion resistance of the material. 展开更多
关键词 sintering atmosphere corrosion resistance NiFe2O4-based cermet inert anode aluminum electrolysis
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Prediction of SO_2 Concentration in Urban Atmosphere Based on B-P Neural Network 被引量:1
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作者 姚建 王丽梅 袁野 《Meteorological and Environmental Research》 CAS 2010年第11期9-11,14,共4页
Base on the principle and method of B-P neural network,the prediction model of SO2 concentration in urban atmosphere was established by using the statistical data of a city in southwest China from 1991 to 2009,so as t... Base on the principle and method of B-P neural network,the prediction model of SO2 concentration in urban atmosphere was established by using the statistical data of a city in southwest China from 1991 to 2009,so as to forecast atmospheric SO2 concentration in a city of southwest China.The results showed that B-P neural network applied in the prediction of SO2 concentration in urban atmosphere was reasonable and efficient with high accuracy and wide adaptability,so it was worthy to be popularized. 展开更多
关键词 B-P neural network SO2 concentration in urban atmospheric Prediction model China
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Relative Impacts of Sea Ice Loss and Atmospheric Internal Variability on the Winter Arctic to East Asian Surface Air Temperature Based on Large-Ensemble Simulations with NorESM2 被引量:1
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作者 Shengping HE Helge DRANGE +4 位作者 Tore FUREVIK Huijun WANG Ke FAN Lise Seland GRAFF Yvan J.ORSOLINI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1511-1526,共16页
To quantify the relative contributions of Arctic sea ice and unforced atmospheric internal variability to the “warm Arctic, cold East Asia”(WACE) teleconnection, this study analyses three sets of large-ensemble simu... To quantify the relative contributions of Arctic sea ice and unforced atmospheric internal variability to the “warm Arctic, cold East Asia”(WACE) teleconnection, this study analyses three sets of large-ensemble simulations carried out by the Norwegian Earth System Model with a coupled atmosphere–land surface model, forced by seasonal sea ice conditions from preindustrial, present-day, and future periods. Each ensemble member within the same set uses the same forcing but with small perturbations to the atmospheric initial state. Hence, the difference between the present-day(or future) ensemble mean and the preindustrial ensemble mean provides the ice-loss-induced response, while the difference of the individual members within the present-day(or future) set is the effect of atmospheric internal variability. Results indicate that both present-day and future sea ice loss can force a negative phase of the Arctic Oscillation with a WACE pattern in winter. The magnitude of ice-induced Arctic warming is over four(ten) times larger than the ice-induced East Asian cooling in the present-day(future) experiment;the latter having a magnitude that is about 30% of the observed cooling. Sea ice loss contributes about 60%(80%) to the Arctic winter warming in the present-day(future) experiment. Atmospheric internal variability can also induce a WACE pattern with comparable magnitudes between the Arctic and East Asia. Ice-lossinduced East Asian cooling can easily be masked by atmospheric internal variability effects because random atmospheric internal variability may induce a larger magnitude warming. The observed WACE pattern occurs as a result of both Arctic sea ice loss and atmospheric internal variability, with the former dominating Arctic warming and the latter dominating East Asian cooling. 展开更多
关键词 Arctic sea ice loss warm Arctic–cold East Asia atmospheric internal variability large-ensemble simulation NorESM2 PAMIP
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Response of seedlings growth of Pinus sylvestriformis to atmospheric CO_2 enrichment in Changbai Mountain 被引量:3
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作者 韩士杰 王琛瑞 +3 位作者 张军辉 邹春静 周玉梅 王晓春 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第4期207-208,共2页
The biomass and ratio of root-shoot of Pinus sylvestfthermis seedlings at Co, concentration of 700 μL L-1 and 50 μL-1L-1 were measured using open-top chambers (OTCs) in Changbai Mountain during Jun. to oct. in 1999.... The biomass and ratio of root-shoot of Pinus sylvestfthermis seedlings at Co, concentration of 700 μL L-1 and 50 μL-1L-1 were measured using open-top chambers (OTCs) in Changbai Mountain during Jun. to oct. in 1999. The results showed that doubling CO2 concentration was benefit tb seedling growth of the species (500 μL- L1 was better than 700 μLL’ L-1 ) and the biomass production was increased in both aboveground and underground parts of seedlings. Carbon trans formation to roots was evident as rising of CO2 concentration. 展开更多
关键词 Pinus sylvestriformis Biomass allocation atmospheric CO_2 enrichment
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Effects of Atmospheres and Precursors on MnO_x/TiO_2 Catalysts for NH_3-SCR at Low Temperature 被引量:9
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作者 方德 HE Feng +2 位作者 谢峻林 FU Zhengbing CHEN Junfu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第5期888-892,共5页
The effects of atmospheres and precursors on MnOx/TiO2 catalysts were studied, which were prepared by the impregnation method and tested for their NOx conversion activity in ammonia selective catalytic reduction (NH3... The effects of atmospheres and precursors on MnOx/TiO2 catalysts were studied, which were prepared by the impregnation method and tested for their NOx conversion activity in ammonia selective catalytic reduction (NH3-SCR) reactions. Results showed that the manganese carbonate (MC) precursor caused mainly Mn2O3, while the manganese nitrate (MN) precursor resulted primarily in MnO2 and the manganese sulfate (MS) precursor was unchanged. The manganese acetate (MA) precursor leaded obtaining a mixture of Mn2O3 and Mn304. NOn conversion decreased in the following order: MA/TiO2 〉 MC/TiO2 〉 MN/TiO2 〉 MS/TiO2 〉 P25, with a calcination temperature of 773 K in air. Catalysts that were prepared by MA and calcined in oxygen performed strong interaction between Ti and Mn, while MnTiO3 was observed. Compared to the catalysts calcined in nitrogen, those calcined in oxygen had larger diameter and smaller surface area and pore. Catalysts that were prepared by MA and calcined in nitrogen tended to gain higher denitration rates than those in air, since they could be prepared with significant specific surface areas. NO., conversion decreased with calcination atmospheres: Nitrogen〉 Air〉 Oxygen. Meanwhile, amorphous Mn2O3 turned into crystalline Mn2O3, when the temperatures increased from 673 to 873 K. 展开更多
关键词 MnOx/TiO2 catalyst PRECURSOR atmosphere NH3-SCR
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Glacial-Interglacial Atmospheric CO_2 Change——The Glacial Burial Hypothesis 被引量:2
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作者 Ning ZENG Department of Meteorology and Earth System Science Interdisciplinary Center, University of Maryland, USA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第5期677-693,共17页
Organic carbon buried under the great ice sheets of the Northern Hemisphere is suggested to be the missing link in the atmospheric CO<SUB>2</SUB> change over the glacial-interglacial cycles. At glaciation,... Organic carbon buried under the great ice sheets of the Northern Hemisphere is suggested to be the missing link in the atmospheric CO<SUB>2</SUB> change over the glacial-interglacial cycles. At glaciation, the advancement of continental ice sheets buries vegetation and soil carbon accumulated during warmer periods. At deglaciation, this burial carbon is released back into the atmosphere. In a simulation over two glacial-interglacial cycles using a synchronously coupled atmosphere-land-ocean carbon model forced by reconstructed climate change, it is found that there is a 547-Gt terrestrial carbon release from glacial maximum to interglacial, resulting in a 60-Gt (about 30-ppmv) increase in the atmospheric CO<SUB>2</SUB>, with the remainder absorbed by the ocean in a scenario in which ocean acts as a passive buffer. This is in contrast to previous estimates of a land uptake at deglaciation. This carbon source originates from glacial burial, continental shelf, and other land areas in response to changes in ice cover, sea level, and climate. The input of light isotope enriched terrestrial carbon causes atmospheric &#948;<SUP>13</SUP>C to drop by about 0.3‰ at deglaciation, followed by a rapid rise towards a high interglacial value in response to oceanic warming and regrowth on land. Together with other ocean based mechanisms such as change in ocean temperature, the glacial burial hypothesis may offer a full explanation of the observed 80–100-ppmv atmospheric CO<SUB>2</SUB> change. 展开更多
关键词 atmospheric CO2 ice age glacial burial hypothesis CLIMATE
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Capability of Raman lidar for monitoring the variation of atmospheric CO_2 profile 被引量:4
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作者 赵培涛 张寅超 +5 位作者 王莲 胡顺星 苏嘉 曹开法 赵曰峰 胡欢陵 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第1期335-342,共8页
Lidar (Light detection and ranging) has special capabilities for remote sensing of many different behaviours of the atmosphere. One of the techniques which show a great deal of promise for several applications is Ra... Lidar (Light detection and ranging) has special capabilities for remote sensing of many different behaviours of the atmosphere. One of the techniques which show a great deal of promise for several applications is Raman scattering. The detecting capability, including maximum operation range and minimum detectable gas concentration is one of the most significant parameters for lidar remote sensing of pollutants. In this paper, based on the new method for evaluating the capabilities of a Raman lidar system, we present an evaluation of detecting capability of Raman lidar for monitoring atmospheric CO2 in Hefei. Numerical simulations about the influence of atmospheric conditions on lidar detecting capability were carried out, and a conclusion can be drawn that the maximum difference of the operation ranges caused by the weather conditions alone can reach about 0.4 to 0.5km with a measuring precision within 30ppmv. The range of minimum detectable concentration caused by the weather conditions alone can reach about 20 to 35 ppmv in vertical direction for 20000 shots at a distance of 1 km on the assumption that other parameters are kept constant. The other corresponding parameters under different conditions are also given. The capability of Raman lidar operated in vertical direction was found to be superior to that operated in horizontal direction. During practical measurement with the Raman lidar whose hardware components were fixed, aerosol scattering extinction effect would be a significant factor that influenced the capability of Raman lidar. This work may be a valuable reference for lidar system designing, measurement accuracy improving and data processing. 展开更多
关键词 Raman lidar atmospheric co2 minimum detectable concentration
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Effects of Sintering Atmosphere on the Microstructure and Surface Properties of Symmetric TiO2 Membranes 被引量:3
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作者 周守勇 仲兆祥 +2 位作者 范益群 徐南平 贺跃辉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第5期739-745,共7页
The effects of sintering atmosphere on the properties of symmetric TiO2 membranes are studied with regard to sintering behavior, porosity, mean pore size, surface comPosition. and surface charge properties. The exerim... The effects of sintering atmosphere on the properties of symmetric TiO2 membranes are studied with regard to sintering behavior, porosity, mean pore size, surface comPosition. and surface charge properties. The exerimental results show that the symmetric TiO2 membranes display better sintering activity in the air than in argon, and the mean pore diameters and porosities of the membrane sintered in argon are higher than those of the membrane sintered in the air at the same temperature. The surface compositions of the symmetric TiO2 membrane sintered in the air and in argon at different temperatures, as studied by X-ray photoelectron spectroscopy, are discussed in terms of their chemical composition, with particular emphasis on the valence state of the titanium ions. The correlation between the valence state of the titanium ions at the surface and the surface charge properties is examined.It is found that the presence of Ti^3+, introduced at the surface of the symmetric TiO2 membranes by sintering in a lower partial pressure of oxygen, is related to a significant decrease in the isoelectric point. TiO2 with Ti^4+ at the interface has an isoelectric point of 5.1, but the non-stoichiometric TiO2-x with Ti^3+ at the interface has a lower isoelectric point of 3.6. 展开更多
关键词 TiO2 membrane sintering atmosphere sintering behavior SURFACE MICROSTRUCTURE
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Using a Tree Ring δ^(13)C Annual Series to Reconstruct Atmospheric CO_2 Concentration over the Past 300 Years 被引量:3
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作者 ZHAO Xing-Yun QIAN Jun-Long +3 位作者 WANG Jian HE Qing-Yan WANG Zu-Liang CHEN Cheng-Zhong 《Pedosphere》 SCIE CAS CSCD 2006年第3期371-379,共9页
The annual series of δ13C were measured in tree rings of three Cryptomeria fortunei disks (OF-1, OF-2, and OF- 3) collected from West Tianmu Mountain, Zhejiang Province, China, according to cross-dating tree ring a... The annual series of δ13C were measured in tree rings of three Cryptomeria fortunei disks (OF-1, OF-2, and OF- 3) collected from West Tianmu Mountain, Zhejiang Province, China, according to cross-dating tree ring ages. There was no obvious decreasing trend of the δ13C annual time series of CF-2 before 1835. However, from 1835 to 1982 the three tree ring δ13C annual series exhibited similar decreasing trends that were significantly (P ≤ 0.001) correlated. The distribution characteristics of a scatter diagram between estimated δ13C series of CF-2 from modeling and the atmospheric CO2 concentration extracted from the Law Dome ice core from 1840 to 1978 were analyzed and a curvilinear regression equation for reconstructing atmospheric CO2 concentration was established with R2 = 0.98. Also, a test of independent samples indicated that between 1685 and 1839 the reconstructed atmospheric CO2 concentration .using the δ13C series of CF-2 had a close relationship with the Law Dome and Siple ice cores, with a standard deviation of 1.98. The general increasing trend of the reconstructed atmospheric CO2 concentration closely reflected the 10ng-term variation of atmospheric CO2 concentration recorded both before and after the Industrial Revolution. Between 1685 and 1840 the evaluated atmospheric CO2 concentration was stable, but after 1840 it exhibited a rapid increase. Given a longer δ13C annual time series of tree rings, it was feasible to rebuild a representative time series to describe the atmospheric CO2 concentration for an earlier period and for years that were not in the ice core record. 展开更多
关键词 atmospheric co2 concentration δ13C RECONSTRUCTION time series tree ring
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The Buffer Capability of the Ocean to Increasing Atmospheric CO_2 被引量:7
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作者 徐永福 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第4期501-510,共10页
The CO_2-seawater system and the method for calculating the partial pressure of CO2 (pCO2) in seawater are studied. The buffer capability of the ocean to increasing atmospheric CO2 is expressed in terms of the differe... The CO_2-seawater system and the method for calculating the partial pressure of CO2 (pCO2) in seawater are studied. The buffer capability of the ocean to increasing atmospheric CO2 is expressed in terms of the differential buffer factor and buffer index. Dissolutions of aragonite and calcite have a significant inffluence on the differential buffer factor. The trend of change in the buffer factor is obtained by a box model. 展开更多
关键词 The Buffer Capability of the Ocean to Increasing atmospheric co2 CO
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CAS-ESM2.0 Successfully Reproduces Historical Atmospheric CO_(2) in a Coupled Carbon−Climate Simulation
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作者 Jiawen ZHU Juanxiong HE +6 位作者 Duoying JI Yangchun LI He ZHANG Minghua ZHANG Xiaodong ZENG Kece FEI Jiangbo JIN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期572-580,共9页
The atmospheric carbon dioxide(CO_(2))concentration has been increasing rapidly since the Industrial Revolution,which has led to unequivocal global warming and crucial environmental change.It is extremely important to... The atmospheric carbon dioxide(CO_(2))concentration has been increasing rapidly since the Industrial Revolution,which has led to unequivocal global warming and crucial environmental change.It is extremely important to investigate the interactions among atmospheric CO_(2),the physical climate system,and the carbon cycle of the underlying surface for a better understanding of the Earth system.Earth system models are widely used to investigate these interactions via coupled carbon-climate simulations.The Chinese Academy of Sciences Earth System Model version 2(CAS-ESM2.0)has successfully fixed a two-way coupling of atmospheric CO_(2)with the climate and carbon cycle on land and in the ocean.Using CAS-ESM2.0,we conducted a coupled carbon-climate simulation by following the CMIP6 proposal of a historical emissions-driven experiment.This paper examines the modeled CO_(2)by comparison with observed CO_(2)at the sites of Mauna Loa and Barrow,and the Greenhouse Gases Observing Satellite(GOSAT)CO_(2)product.The results showed that CAS-ESM2.0 agrees very well with observations in reproducing the increasing trend of annual CO_(2)during the period 1850-2014,and in capturing the seasonal cycle of CO_(2)at the two baseline sites,as well as over northern high latitudes.These agreements illustrate a good ability of CAS-ESM2.0 in simulating carbon-climate interactions,even though uncertainties remain in the processes involved.This paper reports an important stage of the development of CAS-ESM with the coupling of carbon and climate,which will provide significant scientific support for climate research and China’s goal of carbon neutrality. 展开更多
关键词 CAS-ESM atmospheric CO_(2) coupled carbon-climate simulation emissions-driven CMIP6 experiment
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Stress corrosion cracking behavior of high-strength mooring-chain steel in the SO_(2)-polluted coastal atmosphere 被引量:1
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作者 Menghao Liu Zhiyong Liu +3 位作者 Cuiwei Du Xiaoqin Zhan Xiaojia Yang Xiaogang Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第6期1186-1196,共11页
21Cr2NiMo steel is widely used to stabilize offshore oil platforms;however,it suffers from stress-corrosion cracking(SCC).Herein,we studied the SCC behavior of 21Cr2NiMo steel in SO_(2)-polluted coastal atmospheres.El... 21Cr2NiMo steel is widely used to stabilize offshore oil platforms;however,it suffers from stress-corrosion cracking(SCC).Herein,we studied the SCC behavior of 21Cr2NiMo steel in SO_(2)-polluted coastal atmospheres.Electrochemical tests revealed that the addition of SO_(2) increased the corrosion current.Rust characterization showed that SO_(2) addition densified the corrosion products and promoted pitting.Furthermore,slow strain rate tests demonstrated a high susceptibility to SCC in high SO_(2) contents.Fracture morphologies revealed that the stress-corrosion cracks initiated at corrosion pits and the crack propagation showed transgranular and intergranular cracking modes.In conclusion,SCC is mix-controlled by anodic dissolution and hydrogen embrittlement mechanisms. 展开更多
关键词 corrosion marine atmospheres mooring-chain steel SO_(2)-polluted coastal atmospheres stress-corrosion cracking
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Analysis of influence of atmosphere extinction to Raman lidar monitoring CO2 concentration profile 被引量:1
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作者 赵培涛 张寅超 +6 位作者 王莲 赵曰峰 苏嘉 方欣 曹开法 谢军 杜小勇 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第8期2486-2491,共6页
Lidar (Light detection and ranging) system monitoring of the atmosphere is a novel and powerful technique tool. The Raman lidar is well established today as a leading research tool in the study of numerous important... Lidar (Light detection and ranging) system monitoring of the atmosphere is a novel and powerful technique tool. The Raman lidar is well established today as a leading research tool in the study of numerous important areas in the atmospheric sciences. In this paper, the principle of Raman lidar technique measurement CO2 concentration profile is presented and the errors caused by molecular and aerosol extinction for CO2 concentration profile measurement with Raman lidar are also presented. The standard atmosphere extinction profile and 'real-time' Hefei area extinction profile are used to conduct correction and the corresponding results are yielded. Simulation results with standard atmosphere mode correction indicate that the errors caused by molecule and aerosol extinction should be counted for the reason that they could reach about 8 ppm and 5 ppm respectively. The relative error caused by Hefei area extinction correction could reach about 6%. The errors caused by the two components extinction influence could produce significant changes for CO2 concentration profile and need to be counted in data processing which could improve the measurement accuracies. 展开更多
关键词 Raman lidar atmospheric co2 aerosol extinction molecule extinction
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Effect of sintering atmosphere on composition and properties of NiFe_2O_4 ceramic 被引量:1
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作者 田忠良 张腾 +2 位作者 刘恺 赖延清 李劼 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期450-454,共5页
Ni Fe2O4 ceramics were prepared in different sintering atmospheres. The phase compositions, microstructures and mechanical properties were studied. The results show that the stoichiometric compound Ni Fe2O4 cannot be ... Ni Fe2O4 ceramics were prepared in different sintering atmospheres. The phase compositions, microstructures and mechanical properties were studied. The results show that the stoichiometric compound Ni Fe2O4 cannot be obtained in vacuum or atmospheres with oxygen contents of 2×10-5, 2×10-4 and 2×10-3, respectively. All the samples sintered in above-mentioned atmospheres contain phases of Ni Fe2O4 and Ni O. With increasing oxygen content, Ni Fe2O4 content in the ceramic increases, while Ni O content appears a contrary trend. In vacuum, Ni Fe2O4 ceramic has average grain size of 3.94 μm, and bending strength of85.12 MPa. The changes of the phase composition and mechanical properties of Ni Fe2O4 based cermets are mainly caused by the alteration of their properties of Ni Fe2O4 ceramic. 展开更多
关键词 NiFe2O4 ceramic MICROSTRUCTURE mechanical property sintering atmosphere
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Spatial heterodyne spectroscopy for space-based measurements of atmospheric CO_2 被引量:1
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作者 叶函函 王先华 +3 位作者 李志伟 韦秋叶 施海亮 熊伟 《Journal of Beijing Institute of Technology》 EI CAS 2015年第4期540-545,共6页
To reduce the error from measurement and retrieval process, a new technology of spatial heterodyne spectroscopy is proposed. The principle of this technology and the instrument spatial het- erodyne spectrometer (SHS... To reduce the error from measurement and retrieval process, a new technology of spatial heterodyne spectroscopy is proposed. The principle of this technology and the instrument spatial het- erodyne spectrometer (SHS) are introduced. The first application of this technology will be for CO2 measurements from space on a high spectral observation satellite. The outstanding measurement principle and the priority of combination of retrieval algorithm and three channels ( O2 A-band, CO2 1.58 μm and 2.06 μm bands) are theoretically analyzed and numerically simulated. Experiments u- sing SHS prototype with low spectral resolution of 0. 4 cm -1are carried out for preliminary valida- tion. The measurements show clear CO2 absorption lines and follow the expected signature with the- ory spectrum, and the retrievals agreed well with GOSAT CO2 products, except a small bias of about 4 × 10 ^-6. The results show that the ability of spatial heterodyne spectroscopy for CO2 detecting is ob- vious, and SHS is a competent sensor. 展开更多
关键词 spatial heterodyne spectrometer atmospheric co2 retrieval algorithm ERROR
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Reactions in a Mixture of CH_4 and CO_2 under the Action of Microwave Discharge at Atmospheric Pressure 被引量:1
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作者 Yunpeng Xu Zhijian Tian +1 位作者 Zhusheng Xu Liwu Lin 《Journal of Natural Gas Chemistry》 CAS CSCD 2002年第1期28-32,共5页
Reactions between CH_4 and CO_2 under the action of continuous microwave discharge at atmospheric pressure were studied in a special homemade reactor. The main products were CO and H2, while acetylene and ethylene wer... Reactions between CH_4 and CO_2 under the action of continuous microwave discharge at atmospheric pressure were studied in a special homemade reactor. The main products were CO and H2, while acetylene and ethylene were also found in the products. Experimental results show that conversions of CH4 and CO2 could be higher than 90% without the presence of any catalyst. Effects of CO2/CH4 molar ratio and total flow rate of the feed gas on the reaction were also investigated. 展开更多
关键词 CH_4 CO_2 microwave discharge atmospheric pressure
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An integrated and efficient process for borax preparation and magnetite recovery from soda-ash roasted ludwigite ore under CO–CO_(2)–N_(2) atmosphere 被引量:1
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作者 Jinxiang You Jing Wang +4 位作者 Mingjun Rao Xin Zhang Jun Luo Zhiwei Peng Guanghui Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第11期2169-2181,共13页
To realize the comprehensive utilization of ludwigite ore,an integrated and efficient route for the boron and iron separation was proposed in this work,which via soda-ash roasting under CO–CO_(2)–N_(2) atmosphere fo... To realize the comprehensive utilization of ludwigite ore,an integrated and efficient route for the boron and iron separation was proposed in this work,which via soda-ash roasting under CO–CO_(2)–N_(2) atmosphere followed by grind-leaching,magnetic separation,and CO_(2) carbonation.The effects of roasting temperature,roasting time,CO/(CO+CO_(2))composition,and Na_(2)CO_(3) dosage on the boron and iron separation indices were primarily investigated.Under the optimized conditions of the roasting temperature of 850℃,roasting time of 60 min,soda ash dosage of 20 wt%,and CO/(CO+CO_(2)) of 10 vol%,92%of boron was leached during wet grinding,and 88.6%of iron was recovered during the magnetic separation and magnetic concentrate with a total iron content of 61.51 wt%.Raman spectra and^(11)B NMR results indicated that boron exists asB(OH)_(4)^(-) in the leachate,from which high-purity borax pentahydrate could be prepared by CO_(2) carbonation. 展开更多
关键词 ludwigite ore soda-ash roasting CO-CO_(2)-N_(2)atmosphere BORAX
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Numerical Models and Methods of Atmospheric Parameters Originating in the Formation of the Earth’s Climatic Cycle
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作者 Wend Dolean Arsène Ilboudo Kassoum Yamba +1 位作者 Windé Nongué Daniel Koumbem Issaka Ouédraogo 《Atmospheric and Climate Sciences》 2024年第2期277-286,共10页
Atmospheric models are physical equations based on the ideal gas law. Applied to the atmosphere, this law yields equations for water, vapor (gas), ice, air, humidity, dryness, fire, and heat, thus defining the model o... Atmospheric models are physical equations based on the ideal gas law. Applied to the atmosphere, this law yields equations for water, vapor (gas), ice, air, humidity, dryness, fire, and heat, thus defining the model of key atmospheric parameters. The distribution of these parameters across the entire planet Earth is the origin of the formation of the climatic cycle, which is a normal climatic variation. To do this, the Earth is divided into eight (8) parts according to the number of key parameters to be defined in a physical representation of the model. Following this distribution, numerical models calculate the constants for the formation of water, vapor, ice, dryness, thermal energy (fire), heat, air, and humidity. These models vary in complexity depending on the indirect trigonometric direction and simplicity in the sum of neighboring models. Note that the constants obtained from the equations yield 275.156˚K (2.006˚C) for water, 273.1596˚K (0.00963˚C) for vapor, 273.1633˚K (0.0133˚C) for ice, 0.00365 in/s for atmospheric dryness, 1.996 in<sup>2</sup>/s for humidity, 2.993 in<sup>2</sup>/s for air, 1 J for thermal energy of fire, and 0.9963 J for heat. In summary, this study aims to define the main parameters and natural phenomena contributing to the modification of planetary climate. . 展开更多
关键词 atmospheric Parameter 1 Climatic Cycle 2 Numerical Models 3
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