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废弃煤矿巷道CO_(2)“封存-利用”技术探索及转化效率研究
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作者 来兴平 雷彤 +3 位作者 张楠 胡添龙 介凯 刘旭超 《西安科技大学学报》 北大核心 2026年第1期15-26,共12页
为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧... 为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧化物电解池(SOEC)技术构建巷道反应硐室与实验室微型反应腔之间尺度映射关系,形成室内试验-井下应用的参数对应体系;通过开展恒电流共电解试验以及气相色谱对气体成分分析,系统揭示反应温度与CO_(2)/H_(2)O气体比例对CO_(2)转化效率的影响。结果表明:在保持A/V不变的条件下,巷道反应硐室尺寸为2.4 m×6 m×3.6 m,对应有效反应面积为384 m^(2);法拉第效率随着温度的升高呈现出“先下降后升高”的特征,随着CO_(2)/H_(2)O气体比例的增加而降低,CO_(2)转化率随着温度升高而显著提升,随着CO_(2)/H_(2)O气体比例增加而降低,在温度为850℃、气体比例CO_(2)∶H_(2)O=1∶1的共电解条件下,CO_(2)实现最优转化效率,转化率达72.22%,法拉第效率为61.77%。研究为实现废弃煤矿巷道CO_(2)封存与高值化利用提供了理论依据与技术支撑。 展开更多
关键词 废弃煤矿 固体氧化物电解池 Co_(2)/H_(2)o共电解 法拉第效率 Co_(2)转化率 相似理论
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氮肥减量与追施方式对小麦产量和氮肥利用效率及麦田N_(2)O排放的影响
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作者 石吕 石晓旭 +11 位作者 韩笑 单海勇 刘旭杰 张晋 严旖旎 李赢 刘海翠 魏亚凤 杨美英 薛亚光 刘建 张祖建 《作物学报》 北大核心 2026年第1期202-220,共19页
为探究稻茬小麦深施肥“一基一追”机艺融合技术的增产增效减排机制,2021—2024年在长江下游南通稻茬麦区开展大田试验。试验采用缓释掺混肥料(SRF,N∶P_(2)O_(5)∶K_(2)O=26∶12∶12)和普通尿素(U,46%N),结合自主研发的2BFGK-12(6)260... 为探究稻茬小麦深施肥“一基一追”机艺融合技术的增产增效减排机制,2021—2024年在长江下游南通稻茬麦区开展大田试验。试验采用缓释掺混肥料(SRF,N∶P_(2)O_(5)∶K_(2)O=26∶12∶12)和普通尿素(U,46%N),结合自主研发的2BFGK-12(6)260全秸秆茬地洁区旋耕智能施肥播种机和3ZF-4(200)中耕追肥机,设置7种施肥模式(30 cm+15 cm宽窄行种植):以尿素4次分施(N 240 kg hm^(-2),基肥∶分蘖肥∶拔节肥∶孕穗肥=5∶1∶2∶2,窄行基施,追肥全田撒施)为对照(CK);减氮15%(N 204 kg hm^(-2))条件下设置6种处理:M_(1)(100%SRF窄行基施);M_(2)(60%SRF窄行基施+40%U拔节期窄行撒施);M_(3)(60%SRF窄行基施+40%U返青期宽行条施);M_(4)(60%SRF窄行基施+40%SRF返青期窄行撒施);M_(5)(60%SRF窄行基施+40%SRF返青期宽行条施);M_(4+5)(60%SRF窄行基施+20%SRF返青期宽行条施+20%SRF返青期窄行撒施)。研究比较不同施肥模式对小麦产量效益、根系形态生理、氮素利用效率及N_(2)O排放的影响。结果表明,与CK相比,M_(2)~M_(5)处理提高了小麦产量(4.0%~19.0%)和经济效益(13.7%~35.7%),其中M_(4)和M_(5)处理表现最优,分别增产14.1%和19.0%,经济效益提升34.5%和35.7%。这些处理明显改善了根系特性(根干重密度增加9.7%~111.8%,根系活力和氧化力分别提高6.8%~52.0%和4.2%~44.2%),降低N_(2)O累积排放量22.6%~34.5%,提高0~20 cm土层硝态氮含量11.2%~40.0%。在氮素利用方面,M_(2)~M_(5)处理均提高了籽粒氮素积累量、花后氮素积累量及其对籽粒氮素的贡献率,氮肥利用效率指标(包括偏生产力、农学效率和表观利用率)分别显著提升了22.4%~40.0%、29.7%~74.3%和9.41~18.77个百分点。值得注意的是,M_(4)和M_(5)处理表现出最优的综合效益:N_(2)O累积排放量降幅最大(分别达27.0%和34.5%),氮肥表观利用率2季均维持在43.0%以上(均值分别为43.5%和46.8%),同时在生育后期保持较高的根系活性和耕层无机氮含量。相比之下,M_(1)处理虽然实现了最大的N_(2)O减排效果(降幅35.9%),但导致减产10.4%和经济效益下降10.8%,且氮肥利用效率呈现不稳定的年际变化特征。而优化处理M_(4+5)进一步改善了根系形态生理特性,并提高氮肥表观利用率和籽粒氮素积累量。综上,减氮15%条件下(N 204 kg hm^(-2)),缓混肥2次施用处理(M_(4)和M_(5))能实现产量、经济效益、氮肥利用效率和N_(2)O减排的协同提高,并以追肥深施处理(M_(5))效应更强。本研究为稻茬小麦缓释肥减氮优化高效应用提供重要理论依据。 展开更多
关键词 条带耕作 氮肥减量 追肥方式 产量 氮肥利用 N_(2)o排放
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基于Meta分析的氮肥施用对我国粮田N_(2)O和CH_(4)排放影响研究
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作者 韩莹 张思源 +2 位作者 刘宇 闫秋艳 闫双堆 《核农学报》 北大核心 2026年第2期394-403,I0001-I0004,共14页
为探明氮肥对我国粮田氧化亚氮(N_(2)O)和甲烷(CH_(4))排放的影响,采用Meta分析方法,以粮食作物(小麦、玉米、水稻)主产区为研究对象,比较氮肥施用后不同气候条件、土壤基本理化性质、氮肥管理等因素对土壤N_(2)O、CH_(4)排放及全球增... 为探明氮肥对我国粮田氧化亚氮(N_(2)O)和甲烷(CH_(4))排放的影响,采用Meta分析方法,以粮食作物(小麦、玉米、水稻)主产区为研究对象,比较氮肥施用后不同气候条件、土壤基本理化性质、氮肥管理等因素对土壤N_(2)O、CH_(4)排放及全球增温潜势(GWP)和温室气体排放强度(GHGI)的影响。结果表明,相较于温带和亚热带气候区,在暖温带气候区施用氮肥后的土壤N_(2)O累积排放量、GWP和GHGI增幅最大。自然环境因素中,年均温对土壤N_(2)O累积排放量和GWP影响较大,年降雨量和年日照时数则分别对土壤CH_(4)累积排放量和GHGI影响较大。土壤全氮含量为0.9~1.5 g·kg^(-1)时的土壤N_(2)O累积排放量较高,>1.5 g·kg^(-1)时的CH_(4)累积排放量较高。N_(2)O、CH_(4)累积排放量及GWP和GHGI均在土壤有机质含量15~30 g·kg^(-1)时较高。土壤pH值增加促进温室气体排放。施氮量对土壤N_(2)O累积排放量有显著(P<0.05)正效应。氮肥基肥+追肥施用较一次性基施能有效减少气体排放,且氮肥+生物炭处理的GWP和GHGI增幅均低于秸秆还田和有机肥处理。施用缓控释氮肥比常规化肥产生更少的温室气体。综上所述,在我国种植主要粮食作物时,优化氮肥运筹,即基肥+追肥(基追比5∶5~0∶10,基肥<追肥)、氮肥+生物炭或施用缓控释氮肥均可较常规施用化肥氮有效减少土壤温室气体排放,降低排放强度。本研究结果对我国粮田氮肥的科学施用及温室气体减排具有重要意义。 展开更多
关键词 META分析 氮肥 氧化亚氮(N_(2)o) 甲烷(CH_(4)) 温室气体排放强度(GHGI)
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燃煤烟道气中CO_(2)耦合绿氢制烯烃工艺可行性和技术经济性分析
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作者 李傲 吴华帅 +4 位作者 张效胜 田佳荣 俎浩楠 丁传敏 王俊文 《低碳化学与化工》 北大核心 2026年第1期132-140,共9页
随着能源结构转型和“双碳”战略推进,CO_(2)加氢制烯烃工艺成为碳减排和碳利用的重要途径之一。尽管CO_(2)加氢制烯烃催化剂的实验研究已较为成熟,但其在工业应用方面仍处于起步阶段。借助模拟手段进行工艺分析是实现其工业化的有效途... 随着能源结构转型和“双碳”战略推进,CO_(2)加氢制烯烃工艺成为碳减排和碳利用的重要途径之一。尽管CO_(2)加氢制烯烃催化剂的实验研究已较为成熟,但其在工业应用方面仍处于起步阶段。借助模拟手段进行工艺分析是实现其工业化的有效途径之一。基于CO_(2)加氢制烯烃催化剂,按照70×10^(4)t/a烯烃产能建立了燃煤烟道气中CO_(2)耦合绿氢制烯烃工艺(简称“耦合工艺”),该工艺涵盖多个单元,包括碳捕集、逆水煤气变换反应和费托合成制烯烃反应,以及后续轻烃与重烃的分离过程。模拟结果表明,耦合工艺具有显著的碳减排优势,其碳效率为99.71%,净CO_(2)排放量为-1.83 t/t(生产1 t烯烃的CO_(2)排放量为-1.83 t)。提高CO_(2)转化率可有效降低资本投资和提高能量效率,H_(2)生产成本对耦合工艺的经济可行性有重要影响。当CO_(2)转化率从47%提高至79%时,耦合工艺的能量效率为40.92%,同时总资本投资可降低38.79%。当H_(2)生产成本从0.367 USD/m^(3)(标况)降低至0.114 USD/m^(3),耦合工艺的生产成本(指“烯烃生产成本”)可降低51.58%,最低可降至1006.1 USD/t。在相近的H_(2)生产成本(0.317 USD/m^(3))下,该工艺的生产成本为2100.8 USD/t,优于文献值(3580 USD/t)。 展开更多
关键词 Co_(2)加氢 绿色烯烃 Aspen Plus模拟 工艺可行性分析 经济性分析
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垂向潜流带CO_(2)产量主控因素转变阈值研究
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作者 周诗雨 杨轶群 +3 位作者 戴君一 高迪 李燊琰 王礼春 《地学前缘》 北大核心 2026年第1期25-38,共14页
河流碳排放是全球碳循环的关键环节,潜流带作为其重要组成部分,对碳排放具有显著影响。潜流带CO_(2)产生和排放过程受河流温度和溶解氧(dissolved oxygen,DO)等动态因素控制,然而,目前大多数模型仍基于稳态条件,难以准确捕捉CO_(2)产量... 河流碳排放是全球碳循环的关键环节,潜流带作为其重要组成部分,对碳排放具有显著影响。潜流带CO_(2)产生和排放过程受河流温度和溶解氧(dissolved oxygen,DO)等动态因素控制,然而,目前大多数模型仍基于稳态条件,难以准确捕捉CO_(2)产量动态变化,导致碳排放估算存在较大不确定性。为此,本研究构建了典型沙丘形态的潜流带生物地球化学耦合模型,引入日周期性变化的河流温度和DO,将其作为潜流带边界条件,利用COMSOL Multiphysics对耦合模型进行数值求解,并通过达姆科勒数(Damk hler number,Da)和相关系数来分析河流温度和DO波动边界条件对垂向潜流带CO_(2)产量的动态影响及调控机制。研究结果表明,温度和DO对CO_(2)产生速率具有显著调控作用且存在竞争关系。在潜流带平均滞留时间小于15.7 h时,存在温度阈值,使CO_(2)产生速率的主控因素随河流平均温度发生转换。具体表现为:在温度阈值以下,主控因素为温度波动;而在温度阈值以上,主控因素为DO波动。更为重要的是,当平均滞留时间大于15.7 h时,主控因素转换机制不存在。本研究揭示了河流温度和DO波动对潜流带中CO_(2)产生速率的调控机制,为理解河流碳循环提供了新视角,有助于准确评估潜流带在全球碳循环中的作用,并为预测河流生态系统对气候变化的响应提供理论依据。 展开更多
关键词 潜流带 有氧呼吸 温度阈值 Co_(2) 生物地球化学过程 耦合模型
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Superplastic behavior of fine-grained Ti-10V-2Fe-3Al alloy fabricated by friction stir processing 被引量:1
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作者 Kai Wang Wenjing Zhang +3 位作者 Takuya Ogura Yoshiaki Morisada Xinqing Zhao Hidetoshi Fujii 《Journal of Materials Science & Technology》 2025年第3期26-36,共11页
Ti-10V-2Fe-3Al alloy with fine-grainedβphases was fabricated by friction stir processing with opti-mized processing parameters.The superplastic behavior of the specimens was investigated by tensile deformation at dif... Ti-10V-2Fe-3Al alloy with fine-grainedβphases was fabricated by friction stir processing with opti-mized processing parameters.The superplastic behavior of the specimens was investigated by tensile deformation at different strain rates and temperatures,and an optimal superplastic elongation of 634%was achieved at 700℃ and 3×10^(-4)/s.An annealing treatment at 650℃ for 60 min showed a mi-crostructure withαprecipitates distributed in theβmatrix in the friction stir specimen.Such pre-heat treatment improves the superplasticity of the specimen,achieving an elongation of up to 807%at 750℃ and 3×10^(-4)/s.The influences of tensile temperatures and strain rates on the microstructural evolution,such as grain size variation,grain morphology,and phase transformations,were discussed.The super-plastic deformation behavior of fine-grained Ti-10V-2Fe-3Al alloy is controlled by grain boundary sliding and accompanied by dynamic phase transformation and recrystallization. 展开更多
关键词 Ti-10V-2Fe-3Al alloy Friction stir processing SUPERPLASTICITY Microstructural evolution Pre-heat treatment
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Novel mechanism of the grain boundary diffusion process with Tb based on the discovery of TbFe_(2) phase 被引量:1
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作者 Wendi Zhang Zilong Wang +5 位作者 Xiaojun Sun Weibin Cui Haijun Peng Wenlong Yan Yang Luo Dunbo Yu 《Journal of Materials Science & Technology》 2025年第11期120-129,共10页
The grain boundary diffusion process(GBDP)has proven to be an effective method for enhancing the coercivity of sintered Nd-Fe-B magnets.However,the limited diffusion depth and thicker shell struc-ture have impeded the... The grain boundary diffusion process(GBDP)has proven to be an effective method for enhancing the coercivity of sintered Nd-Fe-B magnets.However,the limited diffusion depth and thicker shell struc-ture have impeded the further development of magnetic properties.Currently,the primary debates re-garding the mechanism of GBDP with Tb revolve around the dissolution-solidification mechanism and the atomic substitution mechanism.To clarify this mechanism,the microstructure evolution of sintered Nd-Fe-B magnets during the heating process of GBDP has been systematically studied by quenching at different tem peratures.In this study,it was found that the formation of TbFe_(2) phase is related to the dis-solution of _(2)Fe_(14)B grains during GBDP with Tb.The theory of mixing heat and phase separation further confirms that the Nd_(2)Fe_(14)B phase dissolves to form a mixed phase of Nd and TbFe_(2),which then solidifies into the(Nd,Tb)_(2)Fe_(14)B phase.Based on the discovery of the TbFe_(2) phase,the dissolution-solidification mechanism is considered the primary mechanism for GBDP.This is supported by the elemental content of the two typical core-shell structures observed. 展开更多
关键词 Grain boundary diffusion process TbFe_(2)phase Dissolution-solidification mechanism Core-shell structure The theory of mixing heat and phase separation
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Sub-monthly Processes Contribute Significantly to CO_(2) Uptake in the South China Sea
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作者 Xiaojing WANG Bo HAN +2 位作者 Gong ZHANG Changwei LIU Qinghua YANG 《Advances in Atmospheric Sciences》 2025年第9期1967-1978,共12页
Estimating the multi-year average air-sea CO_(2) flux over a large area usually involves the use of monthly mean variables from the atmosphere and ocean.Ignoring sub-monthly processes will blur the oceanic carbon cycl... Estimating the multi-year average air-sea CO_(2) flux over a large area usually involves the use of monthly mean variables from the atmosphere and ocean.Ignoring sub-monthly processes will blur the oceanic carbon cycle,especially when the synoptic and sub-seasonal scale processes are significant,like in the South China Sea(SCS).Based on an empirical relationship between the partial pressure of CO_(2) in water and the sea surface temperature(SST),we recalculated the air-sea CO_(2) flux of the SCS with daily products of atmospheric reanalysis and SST.Our results show that the sub-monthly process contributes 10%of the total CO_(2) flux of the SCS and can even alter the sign of the CO_(2) flux in the spring.In the near-surface coupling process,intramonthly variations in surface winds play the dominant role,except in regions with significant ocean eddies.The co-spectrum analysis of SST and wind speed reveals the most essential oscillation of>20 days.Therefore,a product of the sea surface environment for 10-day intervals can better estimate the air-sea CO_(2) flux over the SCS than monthly data. 展开更多
关键词 air-sea Co_(2)flux bulk formula sub-monthly process intraseasonal oscillation
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Machine learning application in thermal CO_(2)hydrogenation:catalyst design,process optimization,and mechanism insights
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作者 Rasoul Salami Tianlong Liu +1 位作者 Xue Han Ying Zheng 《Advanced Powder Materials》 2025年第6期1-40,共40页
The growing demand for carbon neutrality has heightened the focus on CO_(2)hydrogenation as a viable strategy for transforming carbon dioxide into valuable chemicals and fuels.Advanced machine learning(ML)approaches i... The growing demand for carbon neutrality has heightened the focus on CO_(2)hydrogenation as a viable strategy for transforming carbon dioxide into valuable chemicals and fuels.Advanced machine learning(ML)approaches integrate materials science with artificial intelligence,enabling scientists to identify hidden patterns in datasets,make informed decisions,and reduce the need for labor-intensive,repetitive experimentation.This review provides a comprehensive overview of ML applications in the thermocatalytic hydrogenation of CO_(2).Following an introduction to ML tools and workflows,various ML algorithms employed in CO_(2)hydrogenation are systematically categorized and reviewed.Next,the application of ML in catalyst discovery is discussed,highlighting its role in identifying optimal compositions and structures.Then,ML-driven strategies for process optimization,particularly in enhancing CO_(2)conversion and product selectivity,are examined.Studies modeling descriptors,spanning catalyst properties and reaction conditions,to predict catalytic performance are analyzed.Consequently,ML-based mechanistic studies are reviewed to elucidate reaction pathways,identify key intermediates,and optimize catalyst performance.Finally,key challenges and future perspectives in leveraging ML for advancing CO_(2)hydrogenation research are presented. 展开更多
关键词 Co_(2)hydrogenation Machine learning Catalyst discovery process optimization Reaction mechanisms Algorithms DESCRIPToRS
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Optimization of laser cladding FeMnSiCrNi memory alloy coating process based on response surface model and NSGA-2 algorithm
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作者 Yu Zhang Guang-lei Liu +4 位作者 Shu-cong Liu Wen-chao Xue Wei-mei Chen Hai-xia Liu Jian-zhong Zhou 《China Foundry》 2025年第3期311-322,共12页
To solve the problems of deformation,micro-cracks,and residual tensile stress in laser cladding coatings,the technique of laser cladding with Fe-based memory alloy can be considered.However,the process of in-situ synt... To solve the problems of deformation,micro-cracks,and residual tensile stress in laser cladding coatings,the technique of laser cladding with Fe-based memory alloy can be considered.However,the process of in-situ synthesis of Fe-based memory alloy coatings is extremely complex.At present,there is no clear guidance scheme for its preparation process,which limits its promotion and application to some extent.Therefore,in this study,response surface methodology(RSM)was used to model the response surface between the target values and the cladding process parameters.The NSGA-2 algorithm was employed to optimize the process parameters.The results indicate that the composite optimization method consisting of RSM and the NSGA-2 algorithm can establish a more accurate model,with an error of less than 4.5%between the predicted and actual values.Based on this established model,the optimal scheme for process parameters corresponding to different target results can be rapidly obtained.The prepared coating exhibits a uniform structure,with no defects such as pores,cracks,and deformation.The surface roughness and microhardness of the coating are enhanced,the shaping quality of the coating is effectively improved,and the electrochemical corrosion performance of the coating in 3.5%NaCl solution is obviously better than that of the substrate,providing an important guide for engineering applications. 展开更多
关键词 laser cladding shape memory alloy coating response surface method process parameters optimization NSGA-2 algorithm
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Evaluation of micro-dispersion on oil recovery during low-salinity water-alternating-CO_(2)processes in sandstone cores:An integrated experimental approach
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作者 Jia-Xin Wang Leng Tian +5 位作者 Can Huang Xiao-Jiao Deng Daoyong Tony Yang Rui-Heng Wang Jia-Hao Lin Jin-Yang Wei 《Petroleum Science》 2025年第1期277-295,共19页
Low-salinity water(LSW)and CO_(2) could be combined to perform better in a hydrocarbon reservoir due to their synergistic advantages for enhanced oil recovery(EOR);however,its microscopic recovery mechanisms have not ... Low-salinity water(LSW)and CO_(2) could be combined to perform better in a hydrocarbon reservoir due to their synergistic advantages for enhanced oil recovery(EOR);however,its microscopic recovery mechanisms have not been well understood due to the nature of these two fluids and their physical reactions in the presence of reservoir fluids and porous media.In this work,well-designed and inte-grated experiments have been performed for the first time to characterize the in-situ formation of micro-dispersions and identify their EOR roles during a LSW-alternating-CO_(2)(CO_(2)-LSWAG)process under various conditions.Firstly,by measuring water concentration and performing the Fourier transform infrared spectroscopy(FT-IR)analysis,the in-situ formation of micro-dispersions induced by polar and acidic materials was identified.Then,displacement experiments combining with nuclear magnetic resonance(NMR)analysis were performed with two crude oil samples,during which wettability,interfacial tension(IFT),CO_(2) dissolution,and CO_(2) diffusion were quantified.During a CO_(2)-LSWAG pro-cess,the in-situ formed micro-dispersions dictate the oil recovery,while the presence of clay minerals,electrical double-layer(EDL)expansion and multiple ion exchange(MIE)are found to contribute less.Such formed micro-dispersions are induced by CO_(2) via diffusion to mobilize the CO_(2)-diluted oil,alter the rock wettability towards more water-wet,and minimize the density contrast between crude oil and water. 展开更多
关键词 Low-salinity water-alternating-Co_(2)process Micro-dispersion Wettability alteration Clay minerals Electrical double-layer Multiple ion exchange
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Alloying process of Mg-La in NaCl-KCl-MgCl_(2)-LaCl_(3) melts
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作者 Jia ZHAO Zhi-tao SONG Gui-min LU 《Transactions of Nonferrous Metals Society of China》 2025年第11期3919-3932,共14页
The alloying process of Mg-La in NaCl-KCl-MgCl_(2)-LaCl_(3)(NKML)melts during electroreduction was elucidated using electrochemical techniques and deep potential molecular dynamics(DPMD)simulations.In the NKML system,... The alloying process of Mg-La in NaCl-KCl-MgCl_(2)-LaCl_(3)(NKML)melts during electroreduction was elucidated using electrochemical techniques and deep potential molecular dynamics(DPMD)simulations.In the NKML system,the Mg^(2+)/La^(3+)electrodeposition on the tungsten(W)electrode at 973 K was found to be a one-step process.The nucleation of metal ions on the electrode surface followed an instantaneous nucleation mode and was not influenced by the alloying process.The redox potential and underpotential deposition behavior of the metal ions in the NKML system were accurately predicted by the DPMD simulations,confirming the alloying process of the Mg-La.Additionally,scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS)analysis results confirmed that the cathodic deposits consisted of a bright phase and a dark phase,corresponding to the Mg-La alloys and Mg,respectively.The distribution of electrolytic products suggests that the cathodic deposit initially favors the Mg phase,with the Mg-La alloy forming more easily when the Mg source in the melt is depleted. 展开更多
关键词 NaCl-KCl-MgCl_(2)-LaCl_(3)melt Mg-La alloy alloying process ELECTRoREDUCTIoN redox potential
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Migration and morphological transformation of Mn^(2+)and its effect on microbial community in the A^(2)O process
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作者 Xiaohui Xu Jiexiong Zhong +4 位作者 Xinyao Hao Qun Liu Min Lu Xiaohui Guan Lanhe Zhang 《Journal of Environmental Sciences》 2025年第11期404-416,共13页
Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the ... Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the pollutant removal,metal distribution patterns and composition of microbial communities were investigated in a an anaerobic/anoxic/oxic(A^(2)O)process.The results showed that when Mn^(2+)concentration was 5 mg/L,the efficiencies for the removal of chemical oxygen demand(COD),total nitrogen(TN)and total phosphorus(TP)attained remarkable levels of 96%,93%,and 99%,respectively.In the sludge,the distribution pattern of Mn^(2+)concentration was tightly bound extracellular polymeric substances(TB-EPS)>supernatant>loosely bound EPS(LB-EPS)>soluble microbial products(SMP).Mn^(2+)was found to enrich and accumulate in the microorganism cells.In addition,Mn^(2+)was mainly found in residual fractions and reducible fractions of pellet that manganese was present.The pellet was discovered to contain a substantial quantity of manganese,which was present in various oxidation states,including Mn^(4+),Mn^(3+)and Mn^(2+).The escalating levels of Mn^(2+)led to a reduction in the richness and diversity of microbial communities inhabiting various regions of the A^(2)O reactor.Nonetheless,the uniformity experienced only subtle alterations.Proteobacteria and Bacteroidetes emerged as the leading phyla within the microbial ecosystem,experiencing a steady rise in their respective proportions.The dominant bacterial groups,Azospira and Dechromonas,experienced an incremental increase in their relative prevalence,which played a constructive role in the process of pollutant removal. 展开更多
关键词 Manganese ion Anaerobic/anoxic/oxic(A^(2)o)reactor Migration and transformation Morphology Microbial community
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新型倒置A^(2)/O耦联MBR组合工艺处理农村低C/N废水的研究 被引量:1
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作者 韩卫萍 盖磊 《水处理技术》 CAS 北大核心 2025年第1期114-119,共6页
针对农村低C/N污水污染物和营养盐去除率差的问题,以倒置A^(2)/O耦联膜生物反应器(MBR)组合工艺为探究对象,通过控制进水污染物浓度,在中温条件下考察了有机负荷(OLR)对倒置A^(2)/O耦联MBR组合工艺处理农村低C/N污水的影响。结果表明,OL... 针对农村低C/N污水污染物和营养盐去除率差的问题,以倒置A^(2)/O耦联膜生物反应器(MBR)组合工艺为探究对象,通过控制进水污染物浓度,在中温条件下考察了有机负荷(OLR)对倒置A^(2)/O耦联MBR组合工艺处理农村低C/N污水的影响。结果表明,OLR由150 mg/L提高至450 mg/L时,总氮(TN)和溶解性磷酸盐(SOP)去除率分别由67.6%和86.6%提高至72.4%和94.3%,进一步提高OLR降低了组合工艺对污染物和营养盐的去除。此外,OLR能影响新工艺内污泥特征,提高OLR促进了胞外聚合物(EPS)分泌,尤其在OLR为600 mg/L组别内,EPS含量提高至139.6 mg/g。进水OLR对缺氧池内EPS的影响要大于其对厌氧池内EPS的影响。OLR能影响新工艺内污染物和营养盐去除相关关键酶的活性,当OLR为450 mg/L时,污染物和营养盐去除相关关键活性酶最强。研究结果为农村低C/N污水的高效处理提供了理论依据和数据支撑。 展开更多
关键词 农村低C/N污水 倒置A^(2)/o MBR 胞外聚合物 关键酶
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胺吸收体系中CO_(2)催化解吸再生技术的研究进展 被引量:8
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作者 王宁 陆诗建 +4 位作者 刘玲 梁静 刘苗苗 孙梦圆 康国俊 《化工进展》 北大核心 2025年第1期445-464,共20页
人类工业活动造成大气中CO_(2)含量逐渐增加,形成温室效应,导致全球气候异常。碳捕集、利用与封存(CCUS)技术,尤其是CO_(2)化学吸收过程,是实现大规模CO_(2)减排和遏制全球气候变化的最有效的方法之一。然而,由于CO_(2)捕集技术的高能... 人类工业活动造成大气中CO_(2)含量逐渐增加,形成温室效应,导致全球气候异常。碳捕集、利用与封存(CCUS)技术,尤其是CO_(2)化学吸收过程,是实现大规模CO_(2)减排和遏制全球气候变化的最有效的方法之一。然而,由于CO_(2)捕集技术的高能耗高成本是导致CCUS技术无法大规模推广和商业化应用的瓶颈之一。近年来,胺吸收剂催化再生技术作为一种具有大规模应用潜力的CO_(2)捕集节能新技术引起了国内外研究者的广泛关注。本文综述了胺吸收体系中CO_(2)催化解吸再生技术的研究现状,详细介绍了非均相催化剂的种类、特点、优缺点和面临的挑战,阐述了胺溶液中CO_(2)催化解吸反应机理以及Lewis酸、Br?nsted酸和碱性活性位点等在催化反应过程中的作用机制,总结了影响催化剂解吸再生性能的主要因素。最后,全面分析了催化解吸再生技术用于燃烧后CO_(2)捕集的现状,并对未来的研究趋势进行了展望。 展开更多
关键词 燃后碳捕集 化学吸收法 催化再生技术 非均相催化剂 低能耗
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斯洛文尼亚岩溶区草地生长季土壤CO_(2)变化及其降雨效应 被引量:2
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作者 章程 肖琼 +6 位作者 汪进良 孙平安 苗迎 郭永丽 Mitja PRELOVSEK Martin KNEZ Saša MILANOVIĆ 《地球学报》 北大核心 2025年第2期397-408,共12页
土壤CO_(2)是岩溶作用的核心驱动因子,也是研究土壤呼吸及其与大气CO_(2)源汇关系的核心指标。快速的岩溶动力学和碳循环过程及其对生态系统的敏感性,暗示其在现今全球碳循环中仍在发挥积极作用。本文以斯洛文尼亚第纳尔岩溶区典型草地... 土壤CO_(2)是岩溶作用的核心驱动因子,也是研究土壤呼吸及其与大气CO_(2)源汇关系的核心指标。快速的岩溶动力学和碳循环过程及其对生态系统的敏感性,暗示其在现今全球碳循环中仍在发挥积极作用。本文以斯洛文尼亚第纳尔岩溶区典型草地土壤生态系统为例,开展不同深度土壤温度、水分和土壤CO_(2)含量等指标高分辨率在线监测。监测工作在2021年6—9月草地生长季进行,每10 min记录一组数据。结果表明,土下20 cm、30 cm和50 cm土温均值分别为19.69℃、18.54℃和17.42℃,暗示土温随深度增加逐渐变小。土下20 cm、30 cm和50 cm水分含量均值分别为23.2%、21.7%和24.9%。土壤水分变化主要受降雨控制,降雨强度越大,水分上升幅度越大。土下20 cm、30 cm和50 cm土壤CO_(2)变化范围分别为(1884~6705)×10^(–6)、(2088~5516)×10^(–6)、(2771~3606)×10^(–6),均值分别为3578×10^(–6)、3468×10^(–6)、3174×10^(–6)。无雨期间土壤水分显示出白天下降,夜晚基本保持不变的阶梯状下降趋势,受土壤水分控制,土壤CO_(2)多日总体变化呈现锯齿状持续降低趋势。不同降雨条件下均出现土壤CO_(2)向下迁移现象,从强降雨过程初期产生的土壤CO_(2)含量快速下降看,表明雨水入渗产生的脉冲效应导致CO_(2)快速向下迁移,进一步进入下伏岩溶含水层,可为碳酸盐岩溶蚀提供CO_(2)驱动力,比较下降幅度与雨前CO_(2)含量,暗示降雨过程中12%~33%的土壤CO_(2)进入岩溶含水层并参与碳酸盐岩溶蚀。监测结果暗示岩溶作用是陆地生态系统碳循环的横向延伸,具有土壤CO_(2)汇效应,也就是说,岩溶作用过程具有缓解土壤CO_(2)向大气释放功能,即减源效应。因此,在研究岩溶区碳循环及其碳汇效应时,应把植被-土壤-碳酸盐岩溶蚀作为一个整体,从岩溶关键带角度,系统开展监测与研究,以期获得岩溶区碳循环过程的完整认识,揭示其碳汇效应,进一步评估岩溶区碳循环在全球碳循环的作用和应对气候变化中的地位。 展开更多
关键词 土壤Co_(2) 土壤水分 降雨过程 岩溶作用 减源效应 斯洛文尼亚
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膜曝气生物膜反应器污水处理过程N_(2)O排放特性及减排策略 被引量:2
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作者 王亚宜 贺泰来 +3 位作者 李佳 吴巧玉 汪涵 赵立功 《北京工业大学学报》 北大核心 2025年第3期350-358,共9页
膜曝气生物膜反应器(membrane aerated biofilm reactor,MABR)作为一种新型的污水处理技术,因其高效的氮去除能力和较低的N_(2)O排放水平而受到广泛关注。传统污水处理脱氮过程中,硝化反硝化阶段主要通过羟胺氧化、AOB反硝化、异养反硝... 膜曝气生物膜反应器(membrane aerated biofilm reactor,MABR)作为一种新型的污水处理技术,因其高效的氮去除能力和较低的N_(2)O排放水平而受到广泛关注。传统污水处理脱氮过程中,硝化反硝化阶段主要通过羟胺氧化、AOB反硝化、异养反硝化以及化学变化途径产生N_(2)O。MABR处理市政污水较传统曝气方式具有更低的N_(2)O排放潜力,主要得益于MABR特殊的底物异向扩散模式和无泡曝气方式,这会减少N_(2)O产生潜力及排放水平。该文总结了MABR在运行过程中N_(2)O产生与降低途径,讨论了N_(2)O产生和排放的影响因素及控制策略,并对今后研究MABR体系中N_(2)O排放进行了展望,以期说明MABR进一步工程应用在碳减排方面的优势。 展开更多
关键词 膜曝气生物膜反应器(membrane aerated biofilm reactor MABR) N_(2)o 污水处理 温室气体 碳减排 生物脱氮
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CO_(2)驱油地震监测技术的研究现状与进展 被引量:1
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作者 张军华 杨梅 +3 位作者 陈永芮 冯德永 亓亮 李晓晨 《石油地球物理勘探》 北大核心 2025年第2期529-540,共12页
CO_(2)驱油对提高采收率、减少温室气体排放有重要意义,是国家实现“双碳”目标有效手段,其中地震监测技术是关键。文中分析总结了国内外CO_(2)驱油地震监测技术的研究现状和进展,主要包括时移地震可行性分析、一致性处理技术和综合解释... CO_(2)驱油对提高采收率、减少温室气体排放有重要意义,是国家实现“双碳”目标有效手段,其中地震监测技术是关键。文中分析总结了国内外CO_(2)驱油地震监测技术的研究现状和进展,主要包括时移地震可行性分析、一致性处理技术和综合解释等,并重点论述了CO_(2)驱地震监测技术在高89区块的应用。可行性分析是研究区块开展时移地震监测的重要前提,满足油藏地质条件、岩石物理条件和地震条件才能有效地进行时移地震监测。要实现油藏动态监测,基础地震与监测地震(时移地震)的一致性处理也非常重要,需开展时差、振幅、频率、相位等要素的匹配滤波。时移地震综合解释有助于准确预测CO_(2)驱波及范围,叠前主要借助于AVO属性分析方法;叠后基于基础地震与监测地震资料的差值分析仍是主要方法,频率域信息如分频处理、速度频散、低频伴影等也值得使用;基于深度学习的波及范围预测方法方兴未艾,但其运算效率和泛化能力仍有待进一步提高。最后展望了时移地震技术在提高监测精度、开发监测方法、拓展应用市场等方面的发展潜力。 展开更多
关键词 Co_(2)驱油 时移地震 可行性分析 一致性处理 正演模拟 深度学习 波及范围预测
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运行工况对超临界CO_(2)干气密封端面热力学过程及稳态性能影响研究 被引量:1
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作者 江锦波 陈竹鑫 +5 位作者 肖洋溢 彭新 陈源 于辰 孟祥铠 彭旭东 《化工学报》 北大核心 2025年第6期2913-2928,共16页
超临界CO_(2)压缩机干气密封因密封介质在临界点工况附近的物性特殊性和高参数化,密封间隙内介质流动呈现出多相流动、高度湍流化和物性畸变特征。以微段组合型槽干气密封为研究对象构建了轴向力平衡条件下考虑实际流体效应的超临界CO_... 超临界CO_(2)压缩机干气密封因密封介质在临界点工况附近的物性特殊性和高参数化,密封间隙内介质流动呈现出多相流动、高度湍流化和物性畸变特征。以微段组合型槽干气密封为研究对象构建了轴向力平衡条件下考虑实际流体效应的超临界CO_(2)干气密封热动力润滑相变仿真模型,提出了密封端面热力学过程表征方法,研究了转速、进气压力和进气温度等运行工况参数对超临界CO_(2)干气密封端面热力学过程、流场参数和稳态性能的影响。结果表明:进气温度的提高对于抑制密封端面液相凝析效果显著;转速和进气压力的增大只能抑制槽区液相凝析,增大端面非液相区面积,但对密封坝气液混相区影响不大,当进气温度达到320 K和340 K时,端面纯液相区和气液混相区先后消失;提高非液相区面积,对于增大密封气膜刚度是有利的。 展开更多
关键词 超临界Co_(2) 干气密封 相变 工况参数 热力学过程
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