Well integrity technology can effectively ensure the safety of the entire life cycle of oil and gas wells. With the exploration and development of more and more high-temperature, high-pressure, high-yield and deep wel...Well integrity technology can effectively ensure the safety of the entire life cycle of oil and gas wells. With the exploration and development of more and more high-temperature, high-pressure, high-yield and deep wells, and the constantly increasing requirements for safety and environmental protection in various countries, well integrity technology has become a research hot spot in the oil industry. Based on the analysis of the four basic concepts of well integrity: full life cycle, well integrity management system, well barrier, and risk assessment, this article conducts a comparative analysis of the development history of well integrity technologies at home and abroad, and systematically summarizes foreign wells. The current status of integrity technology, based on the above investigation and analysis, puts forward suggestions for the next development direction of well integrity technology, which has certain guiding significance for the development of the integrity of the next step.展开更多
Aiming at the problem that the existing risk assessment methods in China cannot simply and accurately assess the safety risk of gas wells, a rapid semi-quantitative risk assessment method for gas wells under high temp...Aiming at the problem that the existing risk assessment methods in China cannot simply and accurately assess the safety risk of gas wells, a rapid semi-quantitative risk assessment method for gas wells under high temperature and pressure is studied. Based on the rapid risk assessment method of annulus well with pressure in Chevron Company and the existing risk assessment methods, the well barrier and annulus pressure of high temperature and high pressure gas wells are fully considered. A rapid semi-quantitative risk assessment method for high temperature and high pressure gas wells is established, which takes the annulus pressure value, well service life, annulus pressure recovery after pressure relief, reservoir conditions (formation pressure, production) and well CO<sub style="font-family:" white-space:normal;"=""><span style="font-size:12px;font-family:Verdana;">2 </span></sub><span style="font-family:Verdana;">and H</span><sub style="font-family:" white-space:normal;"=""><span style="font-size:12px;font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">S content as the key risk indexes. The method is applied in a gas field, and the risk value and risk grade of a practical well are semi-quantitatively evaluated. The overall risk situation of the well is obtained. The research results provide important technical guidance for the safe production of gas well.</span>展开更多
Pitting corrosion often occurs due to the presence of various corrosive substances,such as CO_(2) and H_(2)S,in the pipe service environment.As a result of this process,the residual strength of oil pipes is reduced an...Pitting corrosion often occurs due to the presence of various corrosive substances,such as CO_(2) and H_(2)S,in the pipe service environment.As a result of this process,the residual strength of oil pipes is reduced and this can compromise the integrity of the entire pipe string.In the present work,a model is introduced on the basis of the API579 standard to determine the so-called stress concentration coefficient.The model accounts for pitting corrosion shapes such as shallow semi-circles,semi-circles,and deep semi-circles.The relationship between the corrosion pit depth and opening diameter and the residual strength of the oil casing is obtained.The results show that the influence of the pit opening diameter on the stress concentration coefficient is smaller than that of the pit depth.For a constant pit opening diameter,the coefficient increases gradually with increasing the pit depth.The compressive strength and internal pressure strength of the carbon steel oil casing decrease accordingly.When the depth of the corrosion pit is relatively small,the growth of the coefficient is slower;when the depth of the corrosion pit increases to a certain value,the increase in stress concentration coefficient becomes obvious.展开更多
ZiYuan3-03(ZY3-03)satellite was launched on July 25,2020,equipped with China’s second-generation laser altimeter for earth observation.In order to preliminarily evaluate the in-orbit performance of the ZY3-03 laser a...ZiYuan3-03(ZY3-03)satellite was launched on July 25,2020,equipped with China’s second-generation laser altimeter for earth observation.In order to preliminarily evaluate the in-orbit performance of the ZY3-03 laser altimeter,the pointing bias calibration based on terrain matching method was adopted.Three tracks of laser data were employed for the ZY3-03 laser altimeter calibration test.Three groups of pointing parameters were obtained respectively,and the mean value of pointing is considered as the optimal calibration result.After calibration,ZY3-03 laser pointing accuracy is greatly improved by the method,and its pointing accuracy is approximately 12.7 arcsec.The first-track laser data on the Black Sea surface is used to evaluate the relative elevation accuracy of ZY3-03 laser altimeter after pointing bias calibration,which is improved from 0.33 m to 0.19 m after calibration.Meanwhile,the absolute elevation accuracy of ZY3-03 laser altimeter after pointing bias calibration is evaluated by the Ground Control Points(GCPs)measured by RTK(Real-Time Kinematic),which is better than 0.5 m in the flat terrain.展开更多
Designing efficient electrocatalysts for the hydrogen evolution reaction （HER） has attracted substantial attention owing to the urgent demand for clean energy to face the energy crisis and subsequent environmental i...Designing efficient electrocatalysts for the hydrogen evolution reaction （HER） has attracted substantial attention owing to the urgent demand for clean energy to face the energy crisis and subsequent environmental issues in the near future. Among the large variety of HER catalysts, molybdenum disulfide （MoS2） has been regarded as the most famous catalyst owing to its abundance, low price, high efficiency, and definite catalytic mechanism. In this study, defect-engineered MoS2 nanowall （NW） catalysts with controllable thickness were fabricated and exhibited a significantly enhanced HER performance. Benefiting from the highly exposed active edge sites and the rough surface accompanied by the robust NW structure, the defect-rich MoS2 NW catalyst with an optimized thickness showed an ultralow onset overpotential of 85 mV, a high current density of 310.6 mA·cm^-2 at η = 300 mV, and a low potential of 95 mV to drive a 10 mA·cm^-2 cathodic current. Additionally, excellent electrochemical stability was realized, making this freestanding NW catalyst a promising candidate for practical water splitting and hydrogen production.展开更多
Detailed and precise urban land-cover maps are crucial for urban-related studies. However, there are limited ways of mapping high-resolution urban land cover over large areas. In this paper, we propose an operational ...Detailed and precise urban land-cover maps are crucial for urban-related studies. However, there are limited ways of mapping high-resolution urban land cover over large areas. In this paper, we propose an operational framework to map urban land cover on the basis of Ziyuan-3 satellite images. Based on this framework, we produced the first high-resolution(2 m) urban land-cover map(Hi-ULCM) covering the 42 major cities of China. The overall accuracy of the Hi-ULCM dataset is 88.55%, of which 14 cities have an overall accuracy of over 90%. Most of the producer’s accuracies and user’s accuracies of the land-cover classes exceed 85%. We further conducted a landscape pattern analysis in the 42 cities based on Hi-ULCM. In terms of the comparison between the 42 cities in China, we found that the difference in the land-cover composition of urban areas is related to the climatic characteristics and urbanization levels, e.g., cities with warm climates generally have higher proportions of green spaces. It is also interesting to find that cities with higher urbanization levels are more habitable, in general. From the landscape viewpoint, the geometric complexity of the landscape increases with the urbanization level.Compared with the existing medium-resolution land-cover/use datasets(at a 30-m resolution), HiULCM represents a significant advance in accurately depicting the detailed land-cover footprint within the urban areas of China, and will be of great use for studies of urban ecosystems.展开更多
As the important infrastructures for land mapping and resource monitoring,highresolution remote sensing satellites(HRSS)are urgently demanded for the development of China.In this article,the key technologies of the m...As the important infrastructures for land mapping and resource monitoring,highresolution remote sensing satellites(HRSS)are urgently demanded for the development of China.In this article,the key technologies of the main HRSS are summarized,and these technologies include sensor design,attitude and orbit determination,geometric calibration,imaging model construction,and block adjustment,etc.,which involve the mapping accuracy of HRSS.Finally,the system design of the ZY-3 Satellite(China’s first civil stereoscopic surveying and mapping satellite,to be launched in 2012)is introduced,which mainly include satellite technical specifications and strategies design based on these key technologies research.展开更多
Design and fabrication of earth-abundant electrocatalysts for oxygen evolution reaction(OER)is essential in improving the overall ef-ficiency of water electrolysis.In this work,we proposed a rapid and scalable synthes...Design and fabrication of earth-abundant electrocatalysts for oxygen evolution reaction(OER)is essential in improving the overall ef-ficiency of water electrolysis.In this work,we proposed a rapid and scalable synthesis route for fabricating Prussian blue analogue(PBA)nano cubes with tun able compositi ons and uniform particle size.With the structural ben efits of abu ndant surface sites,facile charge transfer behavior and favorable Co^(2+)-to-Co^(3+)pre-oxidation reaction,fast generation and accumulation of the catalytically active Co3+sites can be achieved for the CoCo PBA nano cubes,leadi ng to remarkable OER activity with simulta neously achieved low overpotential,large anodic current density,small Tafel slope as well as outstanding intrinsic activity.Of note,by performing Iong-term OER operati on,the CoCo PBA nano cubes exhibit a remarkable 5.5-folds performs nee enhan ceme nt,and obvious surface rec on struc-tion and the accumulation of high-valence Co species can be identified,proving the crucial role of pre-oxidation process in boosting the OER catalysis.This work proposed a un iversal approach for the rapid,scalable and con trollable fabricati on of the PBA-based materials,and the elucidation of the pre-oxidation process in facilitating the OER catalysis may provide useful guidanee for designing and optimizing advanced catalysts for energy-related electro-oxidation reactions in the future.展开更多
Supercapacitor electrodes with porous structure based on renewable,eco-friendly and cost-effective materials have caused extensive concern in energy storage fields.Sliced bread,the common food ingredient,mainly contai...Supercapacitor electrodes with porous structure based on renewable,eco-friendly and cost-effective materials have caused extensive concern in energy storage fields.Sliced bread,the common food ingredient,mainly containing glucose polymers,can be a promising candidate to fabricate porous supercapacitor electrodes.Highly porous carbon aerogels by using sliced bread as the raw material were synthesized through a carefully controlled aerogel carbonization-activation process.Interestingly,the specific surface area and the pore size distribution of the porous carbon were controlled by the activation temperature,which result in the varied performance of the carbon aerogel as a supercapacitor.Electrochemical investigation measurements revealed that the hierarchical porous carbon aerogel shows an excellent capacitor behavior for construction of a symmetric supercapacitor,which demonstrated a high specific capacitance of 229 F·g-1 at discharge current of 0.2 A·g-1.In addition,the fabricated supercapacitor displayed excellent capacitance retention of 95.5% over 5000 cycles.展开更多
Environmental pollution and energy crisis are two major global challenges to human beings.Recovering energy from wastewater is considered to be one of the effective approaches to address these two issues synchronously...Environmental pollution and energy crisis are two major global challenges to human beings.Recovering energy from wastewater is considered to be one of the effective approaches to address these two issues synchronously.As the main pollutants in wastewater,toxic heavy metal ions are the potential candidates for energy storage devices with pseudocapacitive behaviors.In this study,toxic metal ions of Cr(VI)and Cu(II)are removed efficiently by chitosan coated oxygen-containing functional carbon nanotubes,and the corresponding equilibrium adsorption capacity is 142.1 and 123.7 mg g^(-1).Followed by carbonization of metal ions-adsorbed adsorbents,Cu-and Cr N-loaded carbon composites can be obtained.Electrochemical measurements show that the supercapacitor electrodes based on Cu-and Cr N-loaded carbon composites have specific capacitance of 144.9 and 114.9 F g^(-1)at2 m V s^(-1),with superior electrochemical properties to pure chitosan coated carbon nanotubes after carbonization.This work demonstrates a new strategy for the resource-utilization of other heavy metal ions for energy devices,and also provides a new way to turn environmental pollutants into clean energy.展开更多
In this work,we fabricated an efficient pre-catalyst based on(Ni,Co)S2solid solution with hierarchical architecture and high porosity to boost urea oxidation reaction and electrocatalytic oxidation of organic small mo...In this work,we fabricated an efficient pre-catalyst based on(Ni,Co)S2solid solution with hierarchical architecture and high porosity to boost urea oxidation reaction and electrocatalytic oxidation of organic small molecules.The interaction between Ni and Co can optimize the electronic structure,resulting in the improved conductivity and accelerated charge transfer rate.The 2D/3D architecture can enrich more active species and endow the mass and electron transport to facilitate the surface oxidation and the following catalytic process.Post-structure and catalytic characterizations confirm the surface oxidation of(Ni,Co)S_(2)during the stability test,and the in-situ formed Co(Ni)based(oxy)hydroxides exhibit superior catalytic activity and facilitated charge transfer ability.As a result,the optimal(Ni,Co)S_(2)solid solution pre-catalyst displays facilitated catalytic behavior and good stability for multifunctional electrocatalytic oxidation,in which a high conversion of benzyl alcohol(97.50%),a good selectivity to benzoic acid(93.78%)and a satisfied faraday efficiency(91.86%)can be achieved.展开更多
The well completion process in oil and gas industry,aiming to build effective exploitation,is divided into acidizing and formation water production process.Oxide scale(OS)formed on the inner wall of the HP-13Cr stainl...The well completion process in oil and gas industry,aiming to build effective exploitation,is divided into acidizing and formation water production process.Oxide scale(OS)formed on the inner wall of the HP-13Cr stainless steel tubes during the hot extrusion process changes the surface roughness.The effects of OS on the corrosion of HP-13Cr stainless steel during well completion process were studied by corrosion measurement,spectra analysis,microscopic observation and numerical simulation.The results indicate that the OS make no change of phase distribution and element composition of corrosion scale,while the increasing OS roughness is the dominant factor for accelerating corrosion rate during the well completion process.In acidizing process,the greater surface roughness OS of HP-13Cr stainless steel increases the corrosion rate obviously due to a larger interfacial area in contact with the aggressive environment.During subsequent formation water production process,the turbulence eddy,formed at locations characterized with greater surface roughness OS,can deteriorate the corrosion scale and accelerate the mass transfer of the corrosive species,resulting in more serious corrosion.展开更多
The development of advanced electrocatalysts for electro-oxidation reactions has attracted much attention because of the critical role of such electrocatalysts in improving the overall efficiency of coupled hydrogen p...The development of advanced electrocatalysts for electro-oxidation reactions has attracted much attention because of the critical role of such electrocatalysts in improving the overall efficiency of coupled hydrogen production.We have developed an efficient lanthanum-dopedα-Ni(OH)_(2) bifunctional catalyst with a 1D-2D-3D hierarchical nanostructure.It shows superior activity and stability in the anodic oxygen evolution reaction(OER)and urea oxidation reaction(UOR).Enrichment of the edge sites and conducting La doping inα-Ni(OH)_(2) phase enable formation and stabilization of abundant local Ni^(3+)ions.This guarantees ultralow onset potentials in electro-oxidation reactions.The 1D-2D-3D hierarchical nanostructure significantly boosts the in situ generation of high-valence active species,which results in efficient and stable OER and UOR performances,and the synergistic merit of doping-induced facile reaction kinetics.Because of the structural benefits of a large surface area,charge-transfer promotion,good structural stability,and bifunctionality,a 1%La-dopedα-Ni(OH)_(2) hierarchical nanostructure gives superior OER and UOR performances with low overpotentials,large catalytic current densities,and excellent operational stability.It is therefore a promising catalyst for use in simultaneous alkaline wastewater treatment and hydrogen production.展开更多
After being launched into orbit,the geometric calibration of a satellite laser altimeter will reduce errors in laser pointing and ranging caused by satellite vibrations during launch,environmental changes,and thermal ...After being launched into orbit,the geometric calibration of a satellite laser altimeter will reduce errors in laser pointing and ranging caused by satellite vibrations during launch,environmental changes,and thermal effects during long-term operation,which guarantees the accuracy of measurement data.In this study,a satellite laser geometric calibration method combining infrared detectors and corner-cube retroreflectors(CCRs)is proposed.First,a CCR-based laser ranging error calibration method was established,and then a laser pointing error calibration model was derived based on a single infrared detector array.Taking GaoFen-7(GF-7)satellite laser beam 2 as the experimental object,laser geometric calibration was realized using an infrared detector and CCR-measured data.Then,the accuracy of the proposed method was compared with that of other calibration methods,the CMLID and the CMSPR.The results show that the accuracy of the proposed calibration method is equivalent to that of the CMLID and higher than that of the CMSPR.Among them,the accuracy of the laser pointing after calibration using the proposed method is better than 0.8 arcsec,and the elevation accuracy of the laser on flat,sloping,and mountainous terrains is better than 0.11 m,0.30 m,and 1.80 m,respectively.展开更多
Fabrication of high-activity electrocatalysts with operational stability is desperately needed to achieve efficient energy conversion.Herein,for the first time,we highlight a novel electrocatalyst based on binary nick...Fabrication of high-activity electrocatalysts with operational stability is desperately needed to achieve efficient energy conversion.Herein,for the first time,we highlight a novel electrocatalyst based on binary nickel iron sulfide solid solution hybrids on carbon cloth for oxygen evolution reaction.Benefitting from the synergistic effect of varied phases and the interfacial connection between(Ni,Fe)S2 and(Ni,Fe)3S4 to accelerate the charge transport,the Ni incorporation to optimize the electronic structure of the hybrids and the downshift of the d-band center to facilitate the desorption of oxygen intermediates,the partial charge-transfer between Fe and Ni to boost the generation of catalytically active Ni3+as well as the unique nanosphere structure to offer enough buffer area for the volume changes during constant redox reactions,the obtained binary nickel iron sulfide hybrids((Ni,Fe)S2/(Ni,Fe)3S4)display high catalytic reactivity with a low overpotential of 210 mV to reach the current density of 10 mA cm-2,and excellent stability with negligible activity deterioration,making the hybrid a promising candidate for electrocatalytic alkaline water oxidation.展开更多
文摘Well integrity technology can effectively ensure the safety of the entire life cycle of oil and gas wells. With the exploration and development of more and more high-temperature, high-pressure, high-yield and deep wells, and the constantly increasing requirements for safety and environmental protection in various countries, well integrity technology has become a research hot spot in the oil industry. Based on the analysis of the four basic concepts of well integrity: full life cycle, well integrity management system, well barrier, and risk assessment, this article conducts a comparative analysis of the development history of well integrity technologies at home and abroad, and systematically summarizes foreign wells. The current status of integrity technology, based on the above investigation and analysis, puts forward suggestions for the next development direction of well integrity technology, which has certain guiding significance for the development of the integrity of the next step.
文摘Aiming at the problem that the existing risk assessment methods in China cannot simply and accurately assess the safety risk of gas wells, a rapid semi-quantitative risk assessment method for gas wells under high temperature and pressure is studied. Based on the rapid risk assessment method of annulus well with pressure in Chevron Company and the existing risk assessment methods, the well barrier and annulus pressure of high temperature and high pressure gas wells are fully considered. A rapid semi-quantitative risk assessment method for high temperature and high pressure gas wells is established, which takes the annulus pressure value, well service life, annulus pressure recovery after pressure relief, reservoir conditions (formation pressure, production) and well CO<sub style="font-family:" white-space:normal;"=""><span style="font-size:12px;font-family:Verdana;">2 </span></sub><span style="font-family:Verdana;">and H</span><sub style="font-family:" white-space:normal;"=""><span style="font-size:12px;font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">S content as the key risk indexes. The method is applied in a gas field, and the risk value and risk grade of a practical well are semi-quantitatively evaluated. The overall risk situation of the well is obtained. The research results provide important technical guidance for the safe production of gas well.</span>
基金supported by CNPC Forward-Looking Basic Strategic Technology Research Projects(Nos.2021DJ6504,2021DJ6501,2021DJ6502&2021DJ0806)received by Bo Zhang.
文摘Pitting corrosion often occurs due to the presence of various corrosive substances,such as CO_(2) and H_(2)S,in the pipe service environment.As a result of this process,the residual strength of oil pipes is reduced and this can compromise the integrity of the entire pipe string.In the present work,a model is introduced on the basis of the API579 standard to determine the so-called stress concentration coefficient.The model accounts for pitting corrosion shapes such as shallow semi-circles,semi-circles,and deep semi-circles.The relationship between the corrosion pit depth and opening diameter and the residual strength of the oil casing is obtained.The results show that the influence of the pit opening diameter on the stress concentration coefficient is smaller than that of the pit depth.For a constant pit opening diameter,the coefficient increases gradually with increasing the pit depth.The compressive strength and internal pressure strength of the carbon steel oil casing decrease accordingly.When the depth of the corrosion pit is relatively small,the growth of the coefficient is slower;when the depth of the corrosion pit increases to a certain value,the increase in stress concentration coefficient becomes obvious.
基金Research and Development of Forest Resources Dynamic Monitoring and Forest Volume Estimation with LiDAR Data(No.2020YFE0200800)High Resolution Remote Sensing,Surveying and Mapping Application Program(No.42-Y30B04-9001-19/21)+4 种基金Active and Passive Composite Mapping and Application Technology with Visible,Infrared and Laser Sensors(No.D040106)Multi-beam Terrain Detection Laser and Its Application Technology(No.D040105)National Natural Science Foundation of China(Nos.41571440,41771360,41971426)Class B Project of Beijing Science and Technology Association Jinqiao Project Seed Fund(No.ZZ19013)Innovative Youth Talents Program,MNR(No.12110600000018003930)。
文摘ZiYuan3-03(ZY3-03)satellite was launched on July 25,2020,equipped with China’s second-generation laser altimeter for earth observation.In order to preliminarily evaluate the in-orbit performance of the ZY3-03 laser altimeter,the pointing bias calibration based on terrain matching method was adopted.Three tracks of laser data were employed for the ZY3-03 laser altimeter calibration test.Three groups of pointing parameters were obtained respectively,and the mean value of pointing is considered as the optimal calibration result.After calibration,ZY3-03 laser pointing accuracy is greatly improved by the method,and its pointing accuracy is approximately 12.7 arcsec.The first-track laser data on the Black Sea surface is used to evaluate the relative elevation accuracy of ZY3-03 laser altimeter after pointing bias calibration,which is improved from 0.33 m to 0.19 m after calibration.Meanwhile,the absolute elevation accuracy of ZY3-03 laser altimeter after pointing bias calibration is evaluated by the Ground Control Points(GCPs)measured by RTK(Real-Time Kinematic),which is better than 0.5 m in the flat terrain.
基金Acknowledgements This work was financially supported by the National Basic Research Program of China （No. 2015CB932302）, the National Natural Science Foundation of China （Nos. 21501112, 21331005, 21401181, U1532265, U1632149, 91422303, and 11321503）, and Natural Science Foundation of Shandong Province （No. ZR2014BQ007）.
文摘Designing efficient electrocatalysts for the hydrogen evolution reaction （HER） has attracted substantial attention owing to the urgent demand for clean energy to face the energy crisis and subsequent environmental issues in the near future. Among the large variety of HER catalysts, molybdenum disulfide （MoS2） has been regarded as the most famous catalyst owing to its abundance, low price, high efficiency, and definite catalytic mechanism. In this study, defect-engineered MoS2 nanowall （NW） catalysts with controllable thickness were fabricated and exhibited a significantly enhanced HER performance. Benefiting from the highly exposed active edge sites and the rough surface accompanied by the robust NW structure, the defect-rich MoS2 NW catalyst with an optimized thickness showed an ultralow onset overpotential of 85 mV, a high current density of 310.6 mA·cm^-2 at η = 300 mV, and a low potential of 95 mV to drive a 10 mA·cm^-2 cathodic current. Additionally, excellent electrochemical stability was realized, making this freestanding NW catalyst a promising candidate for practical water splitting and hydrogen production.
基金supported by the National Natural Science Foundation of China (41771360 and 41971295)the National Program for Support of Top-notch Young Professionals, the Hubei Provincial Natural Science Foundation of China (2017CFA029)the National Key Resarch & Development Program of China (2016YFB0501403)。
文摘Detailed and precise urban land-cover maps are crucial for urban-related studies. However, there are limited ways of mapping high-resolution urban land cover over large areas. In this paper, we propose an operational framework to map urban land cover on the basis of Ziyuan-3 satellite images. Based on this framework, we produced the first high-resolution(2 m) urban land-cover map(Hi-ULCM) covering the 42 major cities of China. The overall accuracy of the Hi-ULCM dataset is 88.55%, of which 14 cities have an overall accuracy of over 90%. Most of the producer’s accuracies and user’s accuracies of the land-cover classes exceed 85%. We further conducted a landscape pattern analysis in the 42 cities based on Hi-ULCM. In terms of the comparison between the 42 cities in China, we found that the difference in the land-cover composition of urban areas is related to the climatic characteristics and urbanization levels, e.g., cities with warm climates generally have higher proportions of green spaces. It is also interesting to find that cities with higher urbanization levels are more habitable, in general. From the landscape viewpoint, the geometric complexity of the landscape increases with the urbanization level.Compared with the existing medium-resolution land-cover/use datasets(at a 30-m resolution), HiULCM represents a significant advance in accurately depicting the detailed land-cover footprint within the urban areas of China, and will be of great use for studies of urban ecosystems.
文摘As the important infrastructures for land mapping and resource monitoring,highresolution remote sensing satellites(HRSS)are urgently demanded for the development of China.In this article,the key technologies of the main HRSS are summarized,and these technologies include sensor design,attitude and orbit determination,geometric calibration,imaging model construction,and block adjustment,etc.,which involve the mapping accuracy of HRSS.Finally,the system design of the ZY-3 Satellite(China’s first civil stereoscopic surveying and mapping satellite,to be launched in 2012)is introduced,which mainly include satellite technical specifications and strategies design based on these key technologies research.
基金supported by the Key Research and Development Program of Shandong Province(No.2019GGX103051)the Natural Scie nee Foun dati on of Sha ndong Provi nee(No.ZR2018JL009)the National Natural Science Foundation of China(No.21927811).
文摘Design and fabrication of earth-abundant electrocatalysts for oxygen evolution reaction(OER)is essential in improving the overall ef-ficiency of water electrolysis.In this work,we proposed a rapid and scalable synthesis route for fabricating Prussian blue analogue(PBA)nano cubes with tun able compositi ons and uniform particle size.With the structural ben efits of abu ndant surface sites,facile charge transfer behavior and favorable Co^(2+)-to-Co^(3+)pre-oxidation reaction,fast generation and accumulation of the catalytically active Co3+sites can be achieved for the CoCo PBA nano cubes,leadi ng to remarkable OER activity with simulta neously achieved low overpotential,large anodic current density,small Tafel slope as well as outstanding intrinsic activity.Of note,by performing Iong-term OER operati on,the CoCo PBA nano cubes exhibit a remarkable 5.5-folds performs nee enhan ceme nt,and obvious surface rec on struc-tion and the accumulation of high-valence Co species can be identified,proving the crucial role of pre-oxidation process in boosting the OER catalysis.This work proposed a un iversal approach for the rapid,scalable and con trollable fabricati on of the PBA-based materials,and the elucidation of the pre-oxidation process in facilitating the OER catalysis may provide useful guidanee for designing and optimizing advanced catalysts for energy-related electro-oxidation reactions in the future.
文摘Supercapacitor electrodes with porous structure based on renewable,eco-friendly and cost-effective materials have caused extensive concern in energy storage fields.Sliced bread,the common food ingredient,mainly containing glucose polymers,can be a promising candidate to fabricate porous supercapacitor electrodes.Highly porous carbon aerogels by using sliced bread as the raw material were synthesized through a carefully controlled aerogel carbonization-activation process.Interestingly,the specific surface area and the pore size distribution of the porous carbon were controlled by the activation temperature,which result in the varied performance of the carbon aerogel as a supercapacitor.Electrochemical investigation measurements revealed that the hierarchical porous carbon aerogel shows an excellent capacitor behavior for construction of a symmetric supercapacitor,which demonstrated a high specific capacitance of 229 F·g-1 at discharge current of 0.2 A·g-1.In addition,the fabricated supercapacitor displayed excellent capacitance retention of 95.5% over 5000 cycles.
基金supported by the National Natural Science Foundation of China(51602182,21535004,21390411)Shandong Provincial Natural Science Foundation(ZR2016EMQ02,ZR2016BP07)
文摘Environmental pollution and energy crisis are two major global challenges to human beings.Recovering energy from wastewater is considered to be one of the effective approaches to address these two issues synchronously.As the main pollutants in wastewater,toxic heavy metal ions are the potential candidates for energy storage devices with pseudocapacitive behaviors.In this study,toxic metal ions of Cr(VI)and Cu(II)are removed efficiently by chitosan coated oxygen-containing functional carbon nanotubes,and the corresponding equilibrium adsorption capacity is 142.1 and 123.7 mg g^(-1).Followed by carbonization of metal ions-adsorbed adsorbents,Cu-and Cr N-loaded carbon composites can be obtained.Electrochemical measurements show that the supercapacitor electrodes based on Cu-and Cr N-loaded carbon composites have specific capacitance of 144.9 and 114.9 F g^(-1)at2 m V s^(-1),with superior electrochemical properties to pure chitosan coated carbon nanotubes after carbonization.This work demonstrates a new strategy for the resource-utilization of other heavy metal ions for energy devices,and also provides a new way to turn environmental pollutants into clean energy.
基金supported by National Natural Science Foundation of China(Nos.21927811,51602182,21808129)the Natural Science Foundation of Shandong Province,China(No.ZR2021ME032)。
文摘In this work,we fabricated an efficient pre-catalyst based on(Ni,Co)S2solid solution with hierarchical architecture and high porosity to boost urea oxidation reaction and electrocatalytic oxidation of organic small molecules.The interaction between Ni and Co can optimize the electronic structure,resulting in the improved conductivity and accelerated charge transfer rate.The 2D/3D architecture can enrich more active species and endow the mass and electron transport to facilitate the surface oxidation and the following catalytic process.Post-structure and catalytic characterizations confirm the surface oxidation of(Ni,Co)S_(2)during the stability test,and the in-situ formed Co(Ni)based(oxy)hydroxides exhibit superior catalytic activity and facilitated charge transfer ability.As a result,the optimal(Ni,Co)S_(2)solid solution pre-catalyst displays facilitated catalytic behavior and good stability for multifunctional electrocatalytic oxidation,in which a high conversion of benzyl alcohol(97.50%),a good selectivity to benzoic acid(93.78%)and a satisfied faraday efficiency(91.86%)can be achieved.
基金financially supported by the National Natural Science Foundation of China(No.U1460202)the National program for the Young Top-notch Professionals+2 种基金the Fundamental Research Funds for the Central Universities(No.N170205002)the National Key Research and Development Program of China(No.2017YFB0702203)the Chinese Postdoctoral Science Foundation(No.01270012810066)。
文摘The well completion process in oil and gas industry,aiming to build effective exploitation,is divided into acidizing and formation water production process.Oxide scale(OS)formed on the inner wall of the HP-13Cr stainless steel tubes during the hot extrusion process changes the surface roughness.The effects of OS on the corrosion of HP-13Cr stainless steel during well completion process were studied by corrosion measurement,spectra analysis,microscopic observation and numerical simulation.The results indicate that the OS make no change of phase distribution and element composition of corrosion scale,while the increasing OS roughness is the dominant factor for accelerating corrosion rate during the well completion process.In acidizing process,the greater surface roughness OS of HP-13Cr stainless steel increases the corrosion rate obviously due to a larger interfacial area in contact with the aggressive environment.During subsequent formation water production process,the turbulence eddy,formed at locations characterized with greater surface roughness OS,can deteriorate the corrosion scale and accelerate the mass transfer of the corrosive species,resulting in more serious corrosion.
基金This work was supported by the Key Research and Development Program of Shandong Province(grant No.2019GGX103051)the Natural Science Foundation of Shandong Province(grant No.ZR2018JL009)the National Natural Science Foundation of China(grant No.21927811).
文摘The development of advanced electrocatalysts for electro-oxidation reactions has attracted much attention because of the critical role of such electrocatalysts in improving the overall efficiency of coupled hydrogen production.We have developed an efficient lanthanum-dopedα-Ni(OH)_(2) bifunctional catalyst with a 1D-2D-3D hierarchical nanostructure.It shows superior activity and stability in the anodic oxygen evolution reaction(OER)and urea oxidation reaction(UOR).Enrichment of the edge sites and conducting La doping inα-Ni(OH)_(2) phase enable formation and stabilization of abundant local Ni^(3+)ions.This guarantees ultralow onset potentials in electro-oxidation reactions.The 1D-2D-3D hierarchical nanostructure significantly boosts the in situ generation of high-valence active species,which results in efficient and stable OER and UOR performances,and the synergistic merit of doping-induced facile reaction kinetics.Because of the structural benefits of a large surface area,charge-transfer promotion,good structural stability,and bifunctionality,a 1%La-dopedα-Ni(OH)_(2) hierarchical nanostructure gives superior OER and UOR performances with low overpotentials,large catalytic current densities,and excellent operational stability.It is therefore a promising catalyst for use in simultaneous alkaline wastewater treatment and hydrogen production.
基金supported by National Key Research and Development Program of China:[Grant Number 2020YFE0200800]National Natural Science Foundation of China:[Grant Number 41971426]+1 种基金Special Funds for Creative Research:[Grant Number 2022C61540]Innovative Youth Talents Program,Ministry of Natural Resources of the People’s Republic of China:[Grant Number 12110600000018003930].
文摘After being launched into orbit,the geometric calibration of a satellite laser altimeter will reduce errors in laser pointing and ranging caused by satellite vibrations during launch,environmental changes,and thermal effects during long-term operation,which guarantees the accuracy of measurement data.In this study,a satellite laser geometric calibration method combining infrared detectors and corner-cube retroreflectors(CCRs)is proposed.First,a CCR-based laser ranging error calibration method was established,and then a laser pointing error calibration model was derived based on a single infrared detector array.Taking GaoFen-7(GF-7)satellite laser beam 2 as the experimental object,laser geometric calibration was realized using an infrared detector and CCR-measured data.Then,the accuracy of the proposed method was compared with that of other calibration methods,the CMLID and the CMSPR.The results show that the accuracy of the proposed calibration method is equivalent to that of the CMLID and higher than that of the CMSPR.Among them,the accuracy of the laser pointing after calibration using the proposed method is better than 0.8 arcsec,and the elevation accuracy of the laser on flat,sloping,and mountainous terrains is better than 0.11 m,0.30 m,and 1.80 m,respectively.
基金supported by the National Natural Science Foundation of China(21535004,51602182,91753111,51372142,21390411)Shandong Provincial Natural Science Foundation,China(ZR2016EMQ02)。
文摘Fabrication of high-activity electrocatalysts with operational stability is desperately needed to achieve efficient energy conversion.Herein,for the first time,we highlight a novel electrocatalyst based on binary nickel iron sulfide solid solution hybrids on carbon cloth for oxygen evolution reaction.Benefitting from the synergistic effect of varied phases and the interfacial connection between(Ni,Fe)S2 and(Ni,Fe)3S4 to accelerate the charge transport,the Ni incorporation to optimize the electronic structure of the hybrids and the downshift of the d-band center to facilitate the desorption of oxygen intermediates,the partial charge-transfer between Fe and Ni to boost the generation of catalytically active Ni3+as well as the unique nanosphere structure to offer enough buffer area for the volume changes during constant redox reactions,the obtained binary nickel iron sulfide hybrids((Ni,Fe)S2/(Ni,Fe)3S4)display high catalytic reactivity with a low overpotential of 210 mV to reach the current density of 10 mA cm-2,and excellent stability with negligible activity deterioration,making the hybrid a promising candidate for electrocatalytic alkaline water oxidation.
