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Differences between lower extremity joint running kinetics captured by marker-based and markerless systems were speed dependent
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作者 Hui Tang Barry Munkasy Li Li 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第4期569-578,共10页
Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical analysis.Recent research has reported the feasibility of markerless systems in motion anal... Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical analysis.Recent research has reported the feasibility of markerless systems in motion analysis but has yet to fully explore their utility for capturing faster movements,such as running.Applied studies using markerless systems in clinical and sports settings are still lacking.Thus,the present study compared running biomechanics estimated by marker-based and markerless systems.Given running speed not only affects sports performance but is also associated with clinical injury prevention,diagnosis,and rehabilitation,we aimed to investigate the effects of speed on the comparison of estimated lower extremity joint moments and powers between markerless and marker-based technologies during treadmill running as a concurrent validating study.Methods:Kinematic data from marker-based/markerless technologies were collected,along with ground reaction force data,from 16 young adults running on an instrumented treadmill at 3 speeds:2.24 m/s,2.91 m/s,and 3.58 m/s(5.0 miles/h,6.5 miles/h,and 8.0 miles/h).Sagittal plane moments and powers of the hip,knee,and ankle were calculated by inverse dynamic methods.Time series analysis and statistical parametric mapping were used to determine system differences.Results:Compared to the marker-based system,the markerless system estimated increased lower extremity joint kinetics with faster speed during the swing phase in most cases.Conclusion:Despite the promising application of markerless technology in clinical settings,systematic markerless overestimation requires focused attention.Based on segment pose estimations,the centers of mass estimated by markerless technologies were farther away from the relevant distal joint centers,which led to greater joint moments and powers estimates by markerless vs.marker-based systems.The differences were amplified by running speed. 展开更多
关键词 BIOMECHANICS Motion capture GAIT Statistical parametric mapping
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Recent advances in intermediate-temperature CO_(2) capture: Materials,technologies and applications
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作者 Chengbo Zhao Leiming Wang +4 位作者 Liang Huang Nicholas M.Musyoka Tianshan Xue Jabor Rabeah Qiang Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期435-452,I0010,共19页
Carbon capture,utilization and storage(CCUS) is widely recognized as a vital strategy for mitigating the impact of human induced climate change.Among various CO_(2) adsorbents,intermediate-temperature solid adsorbents... Carbon capture,utilization and storage(CCUS) is widely recognized as a vital strategy for mitigating the impact of human induced climate change.Among various CO_(2) adsorbents,intermediate-temperature solid adsorbents have garnered significant attention due to their potential applications in hydrogen utilization,specifically in the water gas shift,steam reforming and gasification processes.These processes are crucial for achieving carbon neutrality.While laboratory-level studies have showcased the high adsorption capacity of these materials via various synthesis and modification methods,their practical application in complex industrial environments remains challenging,impeding the commercialization process.This review aims to critically summarize the recent research progress made in intermediatetemperature(200-400℃) solid CO_(2) adsorbents,particularly focusing on indicators such as cyclability,gas selectivity,and formability,which play vital roles in industrial application scenarios.Additionally,we provide an overview of laboratory-level advanced technologies specifically tailored for industrial applications.Furthermore,we highlight several industrial-ready advanced technologies that can pave the way for overcoming the challenges associated with large-scale implementation.The insights provided by this review aim to assist researchers in identifying the most relevant research directions for industrial applications.By promoting advances in the application of solid adsorbents,we strive to facilitate the ultimate goal of achieving carbon neutrality. 展开更多
关键词 INTERMEDIATE-TEMPERATURE CO_(2) capture MGO LDHS INDUSTRIALIZATION
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Highly efficient CO_(2) capture using 2-methylimidazole aqueous solution on laboratory and pilot-scale
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作者 Kun Li Han Tang +5 位作者 Shuangshuang Li Zixuan Huang Bei Liu Chun Deng Changyu Sun Guangjin Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期148-156,共9页
To date,the primary industrial carbon capture approach is still absorption using aqueous solutions of alkanolamines.Here,to pursue a substitute for the amine-based approach to improve the CO_(2) capture efficiency and... To date,the primary industrial carbon capture approach is still absorption using aqueous solutions of alkanolamines.Here,to pursue a substitute for the amine-based approach to improve the CO_(2) capture efficiency and decrease the energy cost further,we report a new carbon capture approach using a 2-methylimidazole(mIm)aqueous solution.The properties and sorption behaviors of this approach have been experimentally investigated.The results show that the mIm solution has higher CO_(2) absorption capacity under relatively higher equilibrium pressure(>130 kPa)and lower desorption heat than the methyldiethanolamine solution.91.6%sorption capacity of mIm solution can be recovered at 353.15 K and 80 kPa.The selectivity for CO_(2)/N_(2) and CO_(2)/CH_(4) can reach an exceptional 7609 and 4324,respectively.Furthermore,the pilot-scale tests were also performed,and the results demonstrate that more than 98%of CO_(2) in the feed gas could be removed and cyclic absorption capacity can reach 1 mol·L^(-1).This work indicates that mIm is an excellent alternative to alkanolamines for carbon capture in the industry. 展开更多
关键词 CO_(2) capture Absorption 2-METHYLIMIDAZOLE Separation Pilot-scale tests
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Research progress of CO_(2) capture and mineralization based on natural minerals
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作者 Chenguang Qian Chunquan Li +5 位作者 Peng Huang Jialin Liang Xin Zhang Jifa Wang Jianbing Wang Zhiming Sun 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1208-1227,共20页
Natural minerals,such as kaolinite,halloysite,montmorillonite,attapulgite,bentonite,sepiolite,forsterite,and wollastonite,have considerable potential for use in CO_(2) capture and mineralization due to their abundant ... Natural minerals,such as kaolinite,halloysite,montmorillonite,attapulgite,bentonite,sepiolite,forsterite,and wollastonite,have considerable potential for use in CO_(2) capture and mineralization due to their abundant reserves,low cost,excellent mechanical prop-erties,and chemical stability.Over the past decades,various methods,such as those involving heat,acid,alkali,organic amine,amino sil-ane,and ionic liquid,have been employed to enhance the CO_(2) capture performance of natural minerals to attain high specific surface area,a large number of pore structures,and rich active sites.Future research on CO_(2) capture by natural minerals will focus on the full utiliza-tion of the properties of natural minerals,adoption of suitable modification methods,and preparation of composite materials with high specific surface area and rich active sites.In addition,we provide a summary of the principle and technical route of direct and indirect mineralization of CO_(2) by natural minerals.This process uses minerals with high calcium and magnesium contents,such as forsterite(Mg_(2)SiO_(4)),serpentine[Mg_(3)Si_(2)O(OH)_(4)],and wollastonite(CaSiO_(3)).The research status of indirect mineralization of CO_(2) using hydro-chloric acid,acetic acid,molten salt,and ammonium salt as media is also introduced in detail.The recovery of additives and high-value-added products during the mineralization process to increase economic benefits is another focus of future research on CO_(2) mineralization by natural minerals. 展开更多
关键词 natural mineral carbon dioxide capture MODIFICATION composite material carbon dioxide mineralization
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CO_(2)capture costs of chemical looping combustion of biomass:A comparison of natural and synthetic oxygen carrier
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作者 Benjamin Fleiß Juraj Priscak +3 位作者 Martin Hammerschmid Josef Fuchs Stefan Müller Hermann Hofbauer 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期296-310,共15页
Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and ... Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology. 展开更多
关键词 Chemical looping combustion BECCS Techno-economic assessment CO_(2)capture costs Oxygen carrier development Synthetic materials ILMENITE
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Quantitative analysis of the morphing wing mechanism of raptors:IMMU-based motion capture system and its application on gestures of a Falco peregrinus
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作者 唐迪 朱力文 +7 位作者 施文熙 刘大伟 杨茵 姚国荣 严森祥 范忠勇 陆祎玮 王思宇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期734-742,共9页
This paper presented a novel tinny motion capture system for measuring bird posture based on inertial and magnetic measurement units that are made up of micromachined gyroscopes, accelerometers, and magnetometers. Mul... This paper presented a novel tinny motion capture system for measuring bird posture based on inertial and magnetic measurement units that are made up of micromachined gyroscopes, accelerometers, and magnetometers. Multiple quaternion-based extended Kalman filters were implemented to estimate the absolute orientations to achieve high accuracy.Under the guidance of ornithology experts, the extending/contracting motions and flapping cycles were recorded using the developed motion capture system, and the orientation of each bone was also analyzed. The captured flapping gesture of the Falco peregrinus is crucial to the motion database of raptors as well as the bionic design. 展开更多
关键词 Falco peregrinus IMMU-based motion capture system flapping gesture
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Regulation of interlayer channels of graphene oxide nanosheets in ultra-thin Pebax mixed-matrix membranes for CO_(2) capture
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作者 Feifan Yang Yuanhang Jin +5 位作者 Jiangying Liu Haipeng Zhu Rong Xu Fenjuan Xiangli Gongping Liu Wanqin Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期257-267,共11页
For the application of carbon capture by membrane process,it is crucial to develop a highly permeable CO_(2)-selective membrane.In this work,we reported an ultra-thin polyether-block-amide(Pebax)mixedmatrix membranes(... For the application of carbon capture by membrane process,it is crucial to develop a highly permeable CO_(2)-selective membrane.In this work,we reported an ultra-thin polyether-block-amide(Pebax)mixedmatrix membranes(MMMs)incorporated by graphene oxide(GO),in which the interlayer channels were regulated to optimize the CO_(2)/N_(2) separation performance.Various membrane preparation conditions were systematically investigated on the influence of the membrane structure and separation performance,including the lateral size of GO nanosheets,GO loading,thermal reduction temperature,and time.The results demonstrated that the precisely regulated interlayer channel of GO nanosheets can rapidly provide CO_(2)-selective transport channels due to the synergetic effects of size sieving and preferential adsorption.The GO/Pebax ultra-thin MMMs exhibited CO_(2)/N_(2) selectivity of 72 and CO_(2) permeance of 400 GPU(1 GPU=106 cm^(3)(STP)·cm^(2)·s^(-1)·cmHg^(-1)),providing a promising candidate for CO_(2) capture. 展开更多
关键词 Mixed-matrix membrane Ultra-thin membrane Pebax Graphene oxide CO_(2) capture
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Low-energy-consumption temperature swing system for CO_(2) capture by combining passive radiative cooling and solar heating
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作者 Ying-Xi Dang Peng Tan +3 位作者 Bin Hu Chen Gu Xiao-Qin Liu Lin-Bing Sun 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期507-515,共9页
Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative coo... Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative cooling.For desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for heating.The heating and cooling processes are completely driven by solar energy.Adsorption tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ones.Furthermore,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple cycles.The present work may inspire the development of new temperature swing procedures with little energy consumption. 展开更多
关键词 CO_(2)capture Solar heating Passive radiative cooling Temperature swing adsorption
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Study on the optimal incident proton energy of ^(7)Li(p,n)^(7)Be neutron source for boron neutron capture therapy
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作者 Yi-Nan Zhu Zuo-Kang Lin +3 位作者 Hai-Yan Yu Ye Dai Zhi-Min Dai Xiao-Han Yu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期170-180,共11页
Boron neutron capture therapy(BNCT)is recognized as a precise binary targeted radiotherapy technique that effectively eliminates tumors through the^(10)B(n,α)^(7)Li nuclear reaction.Among various neutron sources,acce... Boron neutron capture therapy(BNCT)is recognized as a precise binary targeted radiotherapy technique that effectively eliminates tumors through the^(10)B(n,α)^(7)Li nuclear reaction.Among various neutron sources,accelerator-based sources have emerged as particularly promising for BNCT applications.The^(7)Li(p,n)^(7)Be reaction is highly regarded as a potential neutron source for BNCT,owing to its low threshold energy for the reaction,significant neutron yield,appropriate average neutron energy,and additional benefits.This study utilized Monte Carlo simulations to model the physical interactions within a lithium target subjected to proton bombardment,including neutron moderation by an MgF_(2)moderator and subsequent BNCT dose analysis using a Snyder head phantom.The study focused on calculating the yields of epithermal neutrons for various incident proton energies,finding an optimal energy at 2.7 MeV.Furthermore,the Snyder head phantom was employed in dose simulations to validate the effectiveness of this specific incident energy when utilizing a^(7)Li(p,n)^(7)Be neutron source for BNCT purposes. 展开更多
关键词 Boron neutron capture therapy ^(7)Li(p n)7Be neutron source Incident proton energy Monte Carlo simulation
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Context Capture在车辆三维建模中的应用
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作者 张雪冰 韦璐 《佳木斯大学学报(自然科学版)》 CAS 2024年第4期144-147,155,共5页
无人机倾斜摄影技术和Context Capture因具有自动化程度高、建模精度和效率高等特点而被广泛应用于三维建模中。本文使用无人机倾斜摄影技术和Context Capture分别对一辆SUV和一辆三厢轿车进行了三维建模,并对其进行了精度分析。结果表... 无人机倾斜摄影技术和Context Capture因具有自动化程度高、建模精度和效率高等特点而被广泛应用于三维建模中。本文使用无人机倾斜摄影技术和Context Capture分别对一辆SUV和一辆三厢轿车进行了三维建模,并对其进行了精度分析。结果表明,采用多条航线的无人机拍摄策略可以充分捕捉车辆各个侧面的细节信息。使用Context Capture构建的车辆三维模型细节清晰可辨,真实地反映了车辆外形。车辆特征点实测数据与航拍数据之间的最大相对误差为0.9%,确保了车辆三维建模的精度要求。 展开更多
关键词 三维建模 Context capture 无人机倾斜摄影 相机标定
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基于Context Capture多视角影像三维重建技术在藏品数字化中的应用
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作者 邓旭帅 《文物鉴定与鉴赏》 2024年第5期142-145,共4页
藏品是博物馆全部活动的物质基础。在博物馆数字化的浪潮中,藏品数字化是核心,而三维建模是藏品数字化的关键手段。多视角三维重建技术因其设备要求低、灵活性强、操作简单等优点成为藏品建模的重要手段。在考古领域,虽然Context Captur... 藏品是博物馆全部活动的物质基础。在博物馆数字化的浪潮中,藏品数字化是核心,而三维建模是藏品数字化的关键手段。多视角三维重建技术因其设备要求低、灵活性强、操作简单等优点成为藏品建模的重要手段。在考古领域,虽然Context Capture在空三精度、纹理映射质量、模型精度等方面具有优势,但由于其不能直接用于可移动文物建模,因此该软件应用较少。通过对采集到的影像预处理或对模型成果后期处理,使之能够用于文物藏品的建模,并对两种方式的优缺点进行比较。 展开更多
关键词 藏品数字化 Context capture 可移动文物建模
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Development of a target capture sequencing SNP genotyping platform for genetic analysis and genomic breeding in rapeseed 被引量:3
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作者 Xiaodong Li Xumei Liu +11 位作者 Yonghai Fan Shengting Li Mengna Yu Mingchao Qian Yuling Chen Hongqiao Chen Xinchun Li Bei Liu Xinfu Xu Cunmin Qu Jiana Li Kun Lu 《The Crop Journal》 SCIE CSCD 2023年第2期499-510,共12页
Rapeseed(Brassica napus)is an oil crop grown worldwide,making it a key plant species in molecular breeding research.However,the complexity of its polyploid genome increases sequencing costs and reduces sequencing accu... Rapeseed(Brassica napus)is an oil crop grown worldwide,making it a key plant species in molecular breeding research.However,the complexity of its polyploid genome increases sequencing costs and reduces sequencing accuracy.Target capture coupled with high-throughput sequencing is an efficient approach for detecting genetic variation at genomic regions or loci of interest.In this study,588 resequenced accessions of rapeseed were used to develop a target capture sequencing SNP genotyping platform named BnaPan50T.The platform comprised 54,765,with 54,058 resequenced markers from the pan-genome,and 855 variant trait-associated markers for 12 agronomic traits.The capture quality of BnaPan50T was demonstrated well in 12 typical accessions.Compared with a conventional genotyping array,BnaPan50T has a high SNP density and a high proportion of SNPs in unique physical positions and in annotated functional genes,promising wide application.Target capture sequencing and wholegenome resequencing in 90 doubled-haploid lines yielded 60%specificity,78%uniformity within tenfold coverage range,and 93%genotyping accuracy for the platform.BnaPan50T was used to construct a genetic map for quantitative trait loci(QTL)mapping,identify 21 unique QTL,and predict several candidate genes for yield-related traits in multiple environments.A set of 132 core SNP loci was selected from BnaPan50T to construct DNA fingerprints and germplasm identification resources.This study provides genomics resources to support target capture sequencing,genetic analysis and genomic breeding of rapeseed. 展开更多
关键词 RAPESEED Target capture SNP genotyping platform Genomic breeding
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Progress and prospect of carbon dioxide capture, utilization and storage in CNPC oilfields 被引量:2
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作者 SONG Xinmin WANG Feng +2 位作者 MA Desheng GAO Ming ZHANG Yunhai 《Petroleum Exploration and Development》 2023年第1期229-244,共16页
The development history of carbon capture,utilization and storage for enhanced oil recovery(CCUS-EOR)in China is comprehensively reviewed,which consists of three stages:research and exploration,field test and industri... The development history of carbon capture,utilization and storage for enhanced oil recovery(CCUS-EOR)in China is comprehensively reviewed,which consists of three stages:research and exploration,field test and industrial application.The breakthrough understanding of CO_(2) flooding mechanism and field practice in recent years and the corresponding supporting technical achievements of CCUS-EOR project are systematically described.The future development prospects are also pointed out.After nearly 60 years of exploration,the theory of CO_(2) flooding and storage suitable for continental sedimentary reservoirs in China has been innovatively developed.It is suggested that C7–C15 are also important components affecting miscibility of CO_(2) and crude oil.The mechanism of rapid recovery of formation energy by CO_(2) and significant improvement of block productivity and recovery factor has been verified in field tests.The CCUS-EOR reservoir engineering design technology for continental sedimentary reservoir is established.The technology of reservoir engineering parameter design and well spacing optimization has been developed,which focuses on maintaining miscibility to improve oil displacement efficiency and uniform displacement to improve sweep efficiency.The technology of CO_(2) capture,injection and production process,whole-system anticorrosion,storage monitoring and other whole-process supporting technologies have been initially formed.In order to realize the efficient utilization and permanent storage of CO_(2),it is necessary to take the oil reservoir in the oil-water transition zone into consideration,realize the large-scale CO_(2) flooding and storage in the area from single reservoir to the overall structural control system.The oil reservoir in the oil-water transition zone is developed by stable gravity flooding of injecting CO_(2) from structural highs.The research on the storage technology such as the conversion of residual oil and CO_(2) into methane needs to be carried out. 展开更多
关键词 carbon dioxide carbon dioxide capture EOR-utilization and storage oil displacement mechanism storage mechanism injection-production process EOR
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Integrated vacuum pressure swing adsorption and Rectisol process for CO_(2) capture from underground coal gasification syngas 被引量:1
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作者 Jian Wang Yuanhui Shen +2 位作者 Donghui Zhang Zhongli Tang Wenbin Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第5期265-279,共15页
An integrated vacuum pressure swing adsorption(VPSA) and Rectisol process is proposed for CO_(2) capture from underground coal gasification(UCG) syngas. A ten-bed VPSA process with silica gel adsorbent is firstly desi... An integrated vacuum pressure swing adsorption(VPSA) and Rectisol process is proposed for CO_(2) capture from underground coal gasification(UCG) syngas. A ten-bed VPSA process with silica gel adsorbent is firstly designed to pre-separate and capture 74.57% CO_(2) with a CO_(2) purity of 98.35% from UCG syngas(CH_(4)/CO/CO_(2)/H_(2)/N_(2)= 30.77%/6.15%/44.10%/18.46%/0.52%, mole fraction, from Shaar Lake Mine Field,Xinjiang Province, China) with a feed pressure of 3.5 MPa. Subsequently, the Rectisol process is constructed to furtherly remove and capture the residual CO_(2)remained in light product gas from the VPSA process using cryogenic methanol(233.15 K, 100%(mass)) as absorbent. A final purified gas with CO_(2) concentration lower than 3% and a regenerated CO_(2) product with CO_(2) purity higher than 95% were achieved by using the Rectisol process. Comparisons indicate that the energy consumption is deceased from 2.143 MJ·kg^(-1) of the single Rectisol process to 1.008 MJ·kg^(-1) of the integrated VPSA & Rectisol process, which demonstrated that the deployed VPSA was an energy conservation process for CO_(2) capture from UCG syngas. Additionally, the high-value gas(e.g., CH_(4)) loss can be decreased and the effects of key operating parameters on the process performances were detailed. 展开更多
关键词 Underground coal gasification Vacuum pressure swing adsorption Rectisol process CO_(2)capture Integrated process
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Coin-structured tunable beam shaping assembly design for accelerator-based boron neutron capture therapy for tumors at different depths and sizes 被引量:1
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作者 Zhao‑Peng Qiao Yao‑Cheng Hu +5 位作者 Quan‑Xu Jiang Jing‑Jing Fan Isao Murata Rui‑Rui Liu Bo Wang Sheng Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第12期66-76,共11页
In the past decade,boron neutron capture therapy utilizing an accelerator-based neutron source(ABNS)designed primarily for producing epithermal neutrons has been implemented in the treatment of brain tumors and other ... In the past decade,boron neutron capture therapy utilizing an accelerator-based neutron source(ABNS)designed primarily for producing epithermal neutrons has been implemented in the treatment of brain tumors and other cancers.The specifications for designing an epithermal beam are primarily based on the IAEA-TECODC-1223 report,issued in 2001 for reactor neutron sources.Based on this report,the latest perspectives and clinical requirements,we designed an ABNS capable of adjusting the average neutron beam energy.The design was based on a 2.8 MeV,20 mA proton beam bombarding a lithium target to produce neutrons that were subsequently moderated and tuned through a tunable beam shaping assembly(BSA)which can modify the thicknesses and materials of the coin-shaped moderators,back reflectors,filters,and collimators.The simulation results demonstrated that epithermal neutron beams for deep seated tumor treatment,which were generated by utilizing magnesium fluoride with lengths ranging between 28 and 36 cm as the moderator,possessed a treatment depth of 5.6 cm although the neutron flux peak shifts from 4.5 to 1.0 keV.When utilizing a thinner moderator,a less accelerated beam power can meet the treatment requirements.However,higher powers reduced the treatment time.In contrast,employing a thick moderator can reduce the skin dose.In scenarios that required relatively low energy neutron beams,the removal of the thermal neutron filter can raise the thermal neutron flux at the beam port.And the depth of the dose rate peak could be adjusted between 0.25 and 2.20 cm by combining magnesium fluoride and polyethylene coins of different thicknesses.Hence,this device has a better adaptability for the treatment of superficial tumors.Overall,the tunable BSA provides greater flexibility for clinical treatment than common BSA designs that can only adjust the port size. 展开更多
关键词 Boron neutron capture therapy(BNCT) Accelerator-based neutron source(ABNS) Beam shaping assembly(BSA) Treatment depth
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Carbon dioxide capture, enhanced-oil recovery and storage technology and engineering practice in Jilin Oilfield, NE China 被引量:1
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作者 WANG Guofeng 《Petroleum Exploration and Development》 2023年第1期245-254,共10页
This paper systematically presents the established technologies and field applications with respect to research and engineering practice of CO_(2) capture,enhanced oil recovery(EOR),and storage technology in Jilin Oil... This paper systematically presents the established technologies and field applications with respect to research and engineering practice of CO_(2) capture,enhanced oil recovery(EOR),and storage technology in Jilin Oilfield,NE China,and depicts the available series of supporting technologies across the industry chain.Through simulation calculation+pilot test+field application,the adaptability of the technology for capturing CO_(2) with different concentrations in oilfields was confirmed.The low energy-consumption,activated N-methyl diethanolamine(MDEA)decarburization technology based on a new activator was developed,and the operation mode of CO_(2) gas-phase transportation through trunk pipeline network,supercritical injection at wellhead,and produced gas-liquid separated transportation was established.According to different gas source conditions,liquid,supercritical phase,high-pressure dense phase pressurization technologies and facilities were applied to form the downhole injection processes(e.g.gas-tight tubing and coiled tubing)and supporting anti-corrosion and anti-blocking techniques.In the practice of oil displacement,the oil recovery technologies(e.g.conical water-alternating-gas injection,CO_(2) foam flooding,and high gas-oil ratio CO_(2) flooding)and produced fluid processing technologies were developed.Through numerical simulation and field tests,three kinds of CO_(2) cyclic injection technologies(i.e.direct injection,injection after separation and purification,and hybrid injection)were formed,and a 10×10^(4) m^(3)/d cyclic injection station was constructed to achieve"zero emission"of associated gas.The CO_(2) storage safety monitoring technology of carbon flux,fluid composition and carbon isotopic composition was formed.The whole-process anti-corrosion technology with anticorrosive agents supplemented by anticorrosive materials was established.An integrated demonstration area of CO_(2) capture,flooding and storage with high efficiency and low energy-consumption has been built,with a cumulative oil increment of 32×10^(4) t and a CO_(2) storage volume of 250×10^(4) t. 展开更多
关键词 CO_(2)emission CO_(2)capture CO_(2)supercritical injection CO_(2)flooding CO_(2)cyclic injection CO_(2)storage
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摄影测量的技术要求和使用技巧--以Reality Capture软件为例 被引量:1
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作者 周刊 《印刷杂志》 2023年第1期46-48,共3页
一、前言Reality Capture(捕捉现实)是一款摄影测量合成三维模型的软件,通过多组和多角度的图像数据,软件会自动识别图像之间相同的特征点,精确计算出三维图像。Reality Capture已被多个行业领域所使用,一些要求和技巧可以极大地缩短建... 一、前言Reality Capture(捕捉现实)是一款摄影测量合成三维模型的软件,通过多组和多角度的图像数据,软件会自动识别图像之间相同的特征点,精确计算出三维图像。Reality Capture已被多个行业领域所使用,一些要求和技巧可以极大地缩短建模时间,提高三维模型质量。本文就如何获取合格的图像和建模技巧进行分析。 展开更多
关键词 REALITY capture 摄影 测量 图像处理
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Selective capture of Tl2O from flue gas with formation of p-n junction on V_(2)O_(5)-WO_(3)/TiO_(2)catalyst under working conditions
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作者 Jianjun Chen Rongqiang Yin +4 位作者 Gongda Chen Junyu Lang Xiaoping Chen Xuefeng Chu Junhua Li 《Green Energy & Environment》 SCIE EI CSCD 2023年第1期4-9,共6页
Thallium(Tl)compounds,highly toxic to biology,are usually released into flue gas during fossil/minerals combustion,and further distributed in water and soil.In this work,we fundamentally investigated the capture of ga... Thallium(Tl)compounds,highly toxic to biology,are usually released into flue gas during fossil/minerals combustion,and further distributed in water and soil.In this work,we fundamentally investigated the capture of gaseous Tl_(2)O by industrial V2O5-WO3/TiO_(2)catalyst under working condition in Tl-containing flue gas.Experimental and theoretical results indicated that the Tl_(2)O has significant electron-feeding capacity and easily donate electron to unoccupied orbitals of TiO_(2),leading to dismutation of Ti 2p and inartificial formation of p-n junction on TiO_(2)surface,which prompted Tl_(2)O selectively interacted with TiO_(2)in flue gas.Herein,we proposed and verified an effective way to capture gaseous Tl_(2)O,which offered almost the best choice to eliminate Tl emission from flue gas and expanded the function of the TiO_(2)-based catalyst.The formation of p-n junction on commercial V2O5-WO3/TiO_(2)catalyst under working condition was revealed for the first time,which can be a valuable reference for both heterocatalysis and electro/photocatalysis. 展开更多
关键词 TL CATALYST SCR capture p-n junction
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Improved SSZ-13 thin membranes fabricated by seeded-gel approach for efficient CO_(2) capture
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作者 Xingzhong Li Kunlin Yu +3 位作者 Zibo He Bo Liu Rongfei Zhou Weihong Xing 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期273-280,共8页
High-quality standard oil synthetic zeolite-13(SSZ-13) membranes with thickness only ~ 1.0 μm were prepared on tubular supports by the new seeded-gel approach. Seeded-gel approach is simpler than the normal secondary... High-quality standard oil synthetic zeolite-13(SSZ-13) membranes with thickness only ~ 1.0 μm were prepared on tubular supports by the new seeded-gel approach. Seeded-gel approach is simpler than the normal secondary-growth one since adding seeds in the gel is simpler than seeding on the support surface. The synthesis time was greatly reduced from 3.0 to 1.0 d after synthesis modification of gel aging and seed sizes. Low temperature ozone calcination was used for the removal of the organic structural directing agent. The best SSZ-13 membrane displayed CO_(2)permeances of 1.3 × 10^(-6) and 1.5 × 10^(-6) mol·m^(-2)·s^(-1)·Pa^(-1) and CO_(2)/CH_(4) and CO_(2)/N_(2) selectivities of 125 and 27 for equimolar CO_(2)/CH_(4) and CO_(2)/N2mixtures at 0.2 MPa pressure drop and 298 K, respectively. Separation performance of the membrane in the two binary mixtures is higher than that of most zeolite membranes. Three SSZ-13 membranes were reproducibly prepared on tubular supports by seeded-gel approach and the standard deviation ratios of CO_(2) permeance and CO_(2)/CH_(4) selectivity are 12.5% and 7%, respectively. It suggests that this new synthesis approach is creditable. The effects of temperature and pressure on separation performance of the thin SSZ-13 membranes were studied in the two binary mixtures. The tubular SSZ-13 membranes displayed great potentials for CO_(2) capture from natural gas, biogas and flue gas. 展开更多
关键词 Zeolite CHA Zeolite membranes SSZ-13 Gas separation CO_(2)capture Seeded-gel approach
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Measurements of absolute electron capture cross sections in He^(2+)–He and Ne^(8+)–O_(2'), N_(2'), CH_4 collisions
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作者 Pu-Fang Ma Jia-Rong Wang +9 位作者 Zi-Xiao Zhang Tian-Ming Meng Zi-Han Xia Bai-Hui Ren Long Wei Ke Yao Jun Xiao Ya-Ming Zou Bing-Sheng Tu Bao-Ren Wei 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第10期126-135,共10页
The total absolute cross sections of single-and double-electron capture (SEC and DEC) in the collisions of He^(2+)with He and Ne^(8+)with O_(2),N_(2),and CH_(4) were studied in the energy ranges 3.5–50 keV/u and 2.8... The total absolute cross sections of single-and double-electron capture (SEC and DEC) in the collisions of He^(2+)with He and Ne^(8+)with O_(2),N_(2),and CH_(4) were studied in the energy ranges 3.5–50 keV/u and 2.8–40 keV/u,respectively.Through a deep analysis of the experimental systematic uncertainties in the measurement procedure and data evaluation,the error in the experimental results of the SEC cross sections is less than 9%.Within the uncertainties,the present results of the He^(2+)–He collision show good consistency with previous measurements,validating the experimental system and paving the way for precise measurements of EC cross sections for a variety of ions and neutral gases.The present measurements allow for a test of EC theory and provide crucial EC cross section data for the establishment of plasma models in fusion research and astrophysical X-ray studies. 展开更多
关键词 Highly charged ions Cross section Electron capture Charge exchange
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