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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
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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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Enhancing performance of low-temperature processed CsPbI2Br all-inorganic perovskite solar cells using polyethylene oxide-modified TiO_(2) 被引量:1
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作者 Xu Zhao Naitao Gao +2 位作者 Shengcheng Wu Shaozhen Li Sujuan Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期786-794,共9页
CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state d... CsPbX_(3)-based(X=I,Br,Cl)inorganic perovskite solar cells(PSCs)prepared by low-temperature process have attracted much attention because of their low cost and excellent thermal stability.However,the high trap state density and serious charge recombination between low-temperature processed TiO_(2)film and inorganic perovskite layer interface seriously restrict the performance of all-inorganic PSCs.Here a thin polyethylene oxide(PEO)layer is employed to modify TiO_(2)film to passivate traps and promote carrier collection.The impacts of PEO layer on microstructure and photoelectric characteristics of TiO_(2)film and related devices are systematically studied.Characterization results suggest that PEO modification can reduce the surface roughness of TiO_(2)film,decrease its average surface potential,and passivate trap states.At optimal conditions,the champion efficiency of CsPbI_(2)Br PSCs with PEO-modified TiO_(2)(PEO-PSCs)has been improved to 11.24%from 9.03%of reference PSCs.Moreover,the hysteresis behavior and charge recombination have been suppressed in PEO-PSCs. 展开更多
关键词 polyethylene oxide-modified TiO_(2) film low-temperature process CsPbI_(2)Br-based all-inorganic perovskite solar cells photo-voltaic performance
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Crystallization management of CsPbI_(2)Br perovskites by PbAc_(2)-incorporated twice spin-coating process for efficient and stable CsPbI_(2)Br perovskite solar cells
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作者 Yu Liu Kun Lang +6 位作者 Huifang Han Huijing Liu Yao Fu Pengchen Zou Yinhui Lyu Jia Xu Jianxi Yao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期419-428,I0008,共11页
CsPbI_(2)Br perovskite solar cell has been extensively studied due to its exceptional thermal stability and relatively stable perovskite phase structure.However,the presence of bromine leads to a rapid crystallization... CsPbI_(2)Br perovskite solar cell has been extensively studied due to its exceptional thermal stability and relatively stable perovskite phase structure.However,the presence of bromine leads to a rapid crystallization rate of CsPbI_(2)Br films,resulting in small grain size and high defect density.Additionally,CsPbI_(2)Br demonstrates poor light absorption due to its wide bandgap.Therefore,it is crucial to control the crystallization rate and increase the film thickness to reduce defect density,enhance light absorption,and improve photovoltaic performance.In this study,we utilized a PbAc_(2)-incorporated twice spincoating(PTS) process to address these issues.Initially,PbAc_(2) was added to the CsPbI_(2)Br precursor solution to form a CsPbI_(2)Br film,which was then coated with the CsPbI_(2)Br precursor solution to produce the PTS film,Ac^(-)can delay the perovskite crystallization,leading to the formation of thicker and denser CsPbI_(2)Br films.Moreover,lone-pair electrons of the oxygen atom provided by Ac^(-)formed coordination bonds with under-coordinated Pb~(2+) ions to fill halogen ion vacancies,thereby reducing the defect density.Ultimately,the PTS CsPbI_(2)Br device achieved a peak power conversion efficiency(PCE) of 16.19% and maintained 96.7% of its initial PCE over 1500 h at room temperature under 25% relative humidity without any encapsulation. 展开更多
关键词 CsPbI_(2)Br Twice spin-coating process PbAc_(2) Crystallization management Perovskite solar cells
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Application of Feature, Event, and Process Methods to Leakage Scenario Development for Offshore CO_(2) Geological Storage
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作者 Qiang Liu Yanzun Li +2 位作者 Meng Jing Qi Li Guizhen Liu 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第3期608-616,共9页
Offshore carbon dioxide(CO_(2)) geological storage(OCGS) represents a significant strategy for addressing climate change by curtailing greenhouse gas emissions. Nonetheless, the risk of CO_(2) leakage poses a substant... Offshore carbon dioxide(CO_(2)) geological storage(OCGS) represents a significant strategy for addressing climate change by curtailing greenhouse gas emissions. Nonetheless, the risk of CO_(2) leakage poses a substantial concern associated with this technology. This study introduces an innovative approach for establishing OCGS leakage scenarios, involving four pivotal stages, namely, interactive matrix establishment, risk matrix evaluation, cause–effect analysis, and scenario development, which has been implemented in the Pearl River Estuary Basin in China. The initial phase encompassed the establishment of an interaction matrix for OCGS systems based on features, events, and processes. Subsequent risk matrix evaluation and cause–effect analysis identified key system components, specifically CO_(2) injection and faults/features. Building upon this analysis, two leakage risk scenarios were successfully developed, accompanied by the corresponding mitigation measures. In addition, this study introduces the application of scenario development to risk assessment, including scenario numerical simulation and quantitative assessment. Overall, this research positively contributes to the sustainable development and safe operation of OCGS projects and holds potential for further refinement and broader application to diverse geographical environments and project requirements. This comprehensive study provides valuable insights into the establishment of OCGS leakage scenarios and demonstrates their practical application to risk assessment, laying the foundation for promoting the sustainable development and safe operation of ocean CO_(2) geological storage projects while proposing possibilities for future improvements and broader applications to different contexts. 展开更多
关键词 Offshore CO_(2)geological storage Features events and processes Scenario development Interaction matrix Risk matrix assessment
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Study on the Interactivity of Controlled and Automatic Information Processing in L2 Reading
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作者 DONG Tiantian WANG Yong 《Sino-US English Teaching》 2024年第7期314-321,共8页
L2 reading is not only an important channel for people to obtain information and knowledge,but also the main way for people to learn a foreign language.Reading information processing can be divided into controlled pro... L2 reading is not only an important channel for people to obtain information and knowledge,but also the main way for people to learn a foreign language.Reading information processing can be divided into controlled processing and automatic processing.Controlled information processing is a conscious and resource-intensive processing model,while automatic information processing is an unconscious and automatic processing model.This study investigates the characteristics and interactivity of controlled and automatic information processing in L2 reading,and explores the roles of controlled and automatic information processing strategies in improving L2 reading ability.The findings are as follows:(a)controlled and automatic information processing is interactive in L2 reading;and(b)the uses of controlled and automatic information processing strategies are beneficial to the improvement of the reading ability of L2 learners.This study has important theoretical and practical value in improving the efficiency of L2 reading teaching and learning. 展开更多
关键词 L2 reading controlled information processing automatic information processing interactivity
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Ti^(2)AlNb合金研究进展及在航空发动机上应用可行性分析
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作者 裴会平 刘冬 +4 位作者 姚利盼 邵天敏 刘巧沐 刘亮亮 陈乾明 《材料工程》 北大核心 2025年第1期28-44,共17页
Ti_(2)AlNb合金优良的综合高温性能使其有望取代部分镍基合金,作为航空发动机关键结构材料实现发动机自身减重。针对未来高性能航空发动机轻量化设计需求,结合统计对比、对照实验、有限元仿真分析等方法,从材料特性、合金冷/热加工工艺... Ti_(2)AlNb合金优良的综合高温性能使其有望取代部分镍基合金,作为航空发动机关键结构材料实现发动机自身减重。针对未来高性能航空发动机轻量化设计需求,结合统计对比、对照实验、有限元仿真分析等方法,从材料特性、合金冷/热加工工艺性能、减重收益等方面分别进行分析,讨论该合金在航空发动机中应用的优势、潜力以及仍需解决的问题。分析结果表明,该合金在减重方面优势显著,且较好地实现了强度、韧性和塑性的综合匹配,无明显短板;具有可接受的冷、热加工性能,通过变形、铸造等方式均可制备工程可用的大规格零件;应用于机匣等静子件可在镍基高温合金基础上减重35.3%,应用于整体叶盘/轮盘等转子件可在镍基高温合金基础上减重37.3%。 展开更多
关键词 Ti_(2)AlNb 航空发动机 减重 材料特性 加工工艺
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Analysis of the Effect and Influencing Factors of Rural Domestic Sewage Treatment Based on A^(2)O-MBBR Integrated Process
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作者 Wangang WU Aiping WU +2 位作者 Guixiang YUAN Yuyuan ZHOU Junwei LU 《Agricultural Biotechnology》 2024年第2期27-32,共6页
[Objectives] This study was conducted to solve the prominent problems in the treatment of domestic sewage in southern rural areas of China. [Methods] An integrated process treatment mode of anaerobic/anoxic/aerobic mo... [Objectives] This study was conducted to solve the prominent problems in the treatment of domestic sewage in southern rural areas of China. [Methods] An integrated process treatment mode of anaerobic/anoxic/aerobic moving bed biofilm reactor (A 2O-MBBR) was proposed to analyze and study its operating effect and influencing factors. [Results] The A^(2)O-MBBR mode had good COD removal efficiency and nitrogen and phosphorus removal performance, and the water quality index of the effluent met the Class A standard of GB181918-2002. This mode is suitable for treating rural domestic sewage, and has high treatment effects in different operating periods. In spring, the average removal rates of COD, NH_(4)^(+)-N, TN, TP and SS reached (83.53 ± 2.15)%, (89.44 ± 4.97)%, (67.36±18.53)%, (88.22±11.21)% and (91.73±2.25)%, respectively;In the autumn period, the average removal rates of COD, NH_(4)^(+)-N, TN, TP and SS were (83.49±2.64)%, (89.26±9.19)%, (66.05±17.00)%, (87.48±9.68)%, and (91.13±2.35)%. [Conclusions] This study provides theoretical reference and technical support for the popularization and application of A^(2)O-MBBR integrated process. 展开更多
关键词 A^(2)O-MBBR process Rural domestic sewage Nitrogen and phosphorus removal
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STUDY ON PREPARATION OF YBa_2Cu_3O_(7-x) ULTRAFINE POWDERS BY SOL-GEL PROCESS
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作者 袁启华 邬江新 +1 位作者 唐福龙 黄俊 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1994年第4期47-54,共8页
The ultrafine powders of YBa2Cu3O7-x with the size of 100nm were synthesized by Sol-Gel process using cit-rate as complex and ammonium hydroxide to adjust pH of solu-tion. The process of Sol formation and Gel polymeri... The ultrafine powders of YBa2Cu3O7-x with the size of 100nm were synthesized by Sol-Gel process using cit-rate as complex and ammonium hydroxide to adjust pH of solu-tion. The process of Sol formation and Gel polymerization of YBa2Cu3O7-x in the Sol-Gel synthetic reaction has bee studied. The particle size ,pruity, sintering activity and superconducting properties of YBa2Cu3O7-x prepared by Sol-Gel method are better than by solid state reaction. 展开更多
关键词 Sol-Gel process YBa2CU3O7-X ultrafine powders.
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Transition of Y_2BaCuO_5 Phase in Powder Melting Processed YBa_2Cu_3O_(7-x) Superconductors
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作者 冯建情 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第4期620-623,共4页
The morphology and the formation of Y2BaCuO5 phase in powder melting processed YBa2Cu3O7-x superconductors were investigated. The experimental results show the heat treatment can not change the shape of Y2BaCuO5 parti... The morphology and the formation of Y2BaCuO5 phase in powder melting processed YBa2Cu3O7-x superconductors were investigated. The experimental results show the heat treatment can not change the shape of Y2BaCuO5 particles in powder melting processed samples. The formation of round Y2BaCuO5 phase is due to relative content of each constitution of precursor powders in powder melting process. For powder melting process, the excessive liquid phase is eliminated, which restrains the preferred growth of Y2BaCuO5 particles. 展开更多
关键词 MORPHOLOGY powder melting process YBa2CU3O7-X scanning electron microscopy
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Influence of Pressure on the Annealing Process of β-Ca_2SiO_4(C_2S) in Portland Cement
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作者 高云鹏 董琬晴 +1 位作者 李工 刘日平 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第3期48-51,共4页
Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete, mortar, stucco, and non-speciality grout. Dicalcium silicate (Ca2SiO4) is the primary constituent ... Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete, mortar, stucco, and non-speciality grout. Dicalcium silicate (Ca2SiO4) is the primary constituent of a number of different types of cement. The β-Ca2SiO4 phase is metastable at room temperature and will transform into β-Ca2SiO4 at 663K. In this work, Portland cement is annealed at a temperature of 950K under pressures in the range of 0-5.5 CPa. The high pressure experiments are carried out in an apparatus with six anvil tops. The effect of high pressure on the obtaining nano-size β-Ca2SiO4 (C2S) process is investigated by x-ray diffraction and transmission electron microscopy. Experimental results show that the grain size of the C2S decreases with the increase of pressure. The volume fraction of the C2S phase increases with the pressure as the pressure is below 3 CPa, and then decreases (P 〉 3 GPa). The nano-effect is very important to the stabilization of β-Ca2SiO4. The mechanism for the effects of the high pressure on the annealing process of the Portland cement is also discussed. 展开更多
关键词 Ca2SiO4 in Portland Cement Influence of Pressure on the Annealing process of SIO
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STUDY OF PREPARATION AND PROPERTY OF YBa_2Cu_3O_(7-δ)-Ag_x COMPOSITE SUPERCONDUCTORS PREPARED BY SOL-GEL PROCESS
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作者 袁启华 唐福龙 +1 位作者 佟钰 袁润章 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1996年第1期47-51,共5页
YBa2Cu3O7-δ-Agx composite superconductors were prepared by hybrid sintering process using YBa2Cu3O7-δ-Agx ultrafine powder and Ag2O finepower, which were prepared by sol-gel process and precipitation process respect... YBa2Cu3O7-δ-Agx composite superconductors were prepared by hybrid sintering process using YBa2Cu3O7-δ-Agx ultrafine powder and Ag2O finepower, which were prepared by sol-gel process and precipitation process respectively. The effect of the Ag content on superconducting crictical transition temperature of YBa2Cu3O7-δ-Agx was not evident as long as YBa2Cu3O7-δ-Agx can form continuous network. But Ag can increase superconduction crictical current and density of the composite superconductors. The normal state (i.e. non-superconducting state at room temperature) resistivity shows a percolation threshold at 20%-30% Ag, whereas the superconducting net-work shows a percolationthreshold at 70% -80% Ag. 展开更多
关键词 YBa2Cu3O7-δ-Agx superconductors sol-gel process.
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IN-SITU HVEM STUDY ON PHASE TRANSITION OF YBa_2Cu_3O_(7-x) SUPERCONDUCTING COMPOUND IN PROCESS OF HEATING
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作者 王瑞坤 邸秀萱 +4 位作者 王振海 贺庆 俞定安 周和平 王英 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第2期99-103,共5页
In-situ HVEM observation on phase transition of the YBa_2Cu_3O_(7-x) superconducting compound in pro- cess of heating was carried out,and high temperature X-ray diffraction analysis in air and X-ray diffraction phase ... In-situ HVEM observation on phase transition of the YBa_2Cu_3O_(7-x) superconducting compound in pro- cess of heating was carried out,and high temperature X-ray diffraction analysis in air and X-ray diffraction phase analysis for the sample treated in vacuum condition were made.The results showed that the temperature of phase transition is related to oxygen content in the sample and in general,is 100℃ to 120℃ lower in vacu- um condition than in air.At 320℃ to 350℃ twin bands begin to disappear,and some Cu_2O are formed on the surface of the sample and transit from orthorhombic YBa_2Cu_3O_(7-x) to arthorhombic Y_2BaCuO_5 compound. This transition was completed at about 500℃.Above 900℃,this compound consists of the Y_2BaCuO_5, BaCuO_2,Y_2O_3 and some other minor compounds.No phase transition was observed during cooling the sample. 展开更多
关键词 HVEM SUPERCONDUCTING COMPOUND IN process OF HEATING IN-SITU HVEM STUDY ON PHASE TRANSITION OF YBa2Cu3O Cu
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超临界CO_(2)管道停输过程温压及相态变化规律预测
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作者 李欣泽 孙晨 +5 位作者 刘晓飞 邹炜杰 姜星宇 郭良辉 董宝军 邢晓凯 《低碳化学与化工》 北大核心 2025年第1期143-152,共10页
不同于原油、天然气管道,超临界CO_(2)管道在停输过程中,需要关注温度和压力共同作用下的CO_(2)相态变化。掌握停输过程管道各位置流体温压变化关系、初始气化工况点和气化程度,对实现管道安全状态预判具有重要意义。基于中国石油天然... 不同于原油、天然气管道,超临界CO_(2)管道在停输过程中,需要关注温度和压力共同作用下的CO_(2)相态变化。掌握停输过程管道各位置流体温压变化关系、初始气化工况点和气化程度,对实现管道安全状态预判具有重要意义。基于中国石油天然气股份有限公司新疆油田分公司百万吨级超临界CO_(2)管道示范工程KB CO_(2)管道,建立了管道水力热力模型并求解,获得了管道停输后全线压力、温度、密度、持液率及相态变化规律,发现流体密度值与单位温降对应的压降值存在正相关性。基于Peng-Robinson状态方程,得到流体气化前压力、温度和密度变化的函数表达式,该温压关系在CO_(2)相图中为相态迁移路径线的斜率值。该值主要受流体密度影响,流体密度500 kg/m^(3)、650 kg/m^(3)和800 kg/m^(3)对应的斜率值分别为0.213、0.325和0.473。同时,给出了流体初始气化时的温压计算公式和气化后持液率变化预测公式。CO_(2)相图中相态迁移路径线与气液平衡线的交点即为流体初始气化压力和温度点。CO_(2)流体气化后,压力和温度状态点将沿着气液平衡线移动,直到温度降至管道周围土壤环境温度。采用OLGA软件对推导出的计算公式进行了验证,计算值与模拟值的误差在±4.00%以内,说明公式具有较高的准确性。最后应用公式对示范工程停输过程安全状态进行了预测,发现管道起点发生气化时的压力最高,为避免管道任意点发生气化,需在管道压力降至7.0 MPa前进行再启动操作。 展开更多
关键词 超临界CO_(2) 管道输送 停输过程 相变
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多功能A2O与水平潜流湿地在高寒地区的联合应用设计研究
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作者 屈连友 《油气田地面工程》 2025年第1期90-96,共7页
针对高寒地区冬季采用A^(2)O(厌氧-缺氧-好氧)工艺+水平潜流人工湿地联合处理生活污水出水中的氮、磷可能存在超标和污水水质多变等问题,对传统的A^(2)O工艺、水平潜流人工湿地结构进行创新性改进设计:A^(2)O工艺采用厌氧池、缺氧池、... 针对高寒地区冬季采用A^(2)O(厌氧-缺氧-好氧)工艺+水平潜流人工湿地联合处理生活污水出水中的氮、磷可能存在超标和污水水质多变等问题,对传统的A^(2)O工艺、水平潜流人工湿地结构进行创新性改进设计:A^(2)O工艺采用厌氧池、缺氧池、好氧池环绕在圆形竖流沉淀池外围,呈环状布置,减少污水热量损失、改善水力条件、提高微生物活性;厌氧池、缺氧池增设曝气工艺,实现ANO(缺氧-好氧)工艺、APO(厌氧-好氧)工艺、A^(2)O工艺可调式功能;O(好氧)工艺中添加悬浮填料,增加单位池容微生物含量,提高有机物、氮、磷等去除率。人工湿地通过试验优选高效除磷填料、根系发达植被根系深入低水位、填料正反粒度双级配布设,提高了氮、磷去除率和悬浮物截留率;人工湿地低水位进出水可提高冬季池内污水温度。结果表明,强化后的工艺系统不同工况下的实际运行效果达到了预期目标。 展开更多
关键词 高寒地区 A^(2)O工艺 水平潜流人工湿地 集约化 适应性改进
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Influence of forming process on three-dimensional morphology of TiB_2 particles in Al-Ti-B alloys 被引量:10
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作者 李鹏廷 李云国 +1 位作者 聂金凤 刘相法 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期564-570,共7页
A series of Al-Ti-B master alloys were prepared by different preparation routes,and the TiB2 particles in the master alloys were extracted and analyzed.It is found that the forming process has significant influence on... A series of Al-Ti-B master alloys were prepared by different preparation routes,and the TiB2 particles in the master alloys were extracted and analyzed.It is found that the forming process has significant influence on the three-dimensional morphology of TiB2 particles.Different preparation routes result in different reaction forms,which accounts for the morphology variation of TiB2 particles.When the Al-Ti-B master alloy is prepared using "halide salt" route,TiB2 particles exhibit hexagonal platelet morphology and are independent with each other.In addition,the reaction temperature almost does not have influence on the morphology of TiB2 particles.However,TiB2 particles exhibit different morphologies at different reaction temperatures when the master alloys are prepared with Al-3B and Ti sponge.When the master alloy is prepared at 850 ℃,a kind of TiB2 particle agglomeration forms with a size larger than 5 μm.The TiB2 particles change to layered stacking morphology even dendritic morphology with the reaction temperature reaching up to 1200 ℃. 展开更多
关键词 Al-Ti-B alloy TIB2 forming process three-dimensional morphology
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Hot deformation and processing maps of Al_2O_3/Al composites fabricated by flake powder metallurgy 被引量:1
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作者 栾佰峰 邱日盛 +4 位作者 李春红 杨晓芳 李志强 张荻 刘庆 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第4期1056-1063,共8页
The deformation behaviors of Al2O3/Al composites were investigated by compressive tests conducted at temperature of 300-450 °C and strain rates of 0.001-1.0 s-1 with Gleeble-1500 D thermal simulator system. The r... The deformation behaviors of Al2O3/Al composites were investigated by compressive tests conducted at temperature of 300-450 °C and strain rates of 0.001-1.0 s-1 with Gleeble-1500 D thermal simulator system. The results show that the flow stress increases with increasing strain rate and decreasing temperature. The hyperbolic sine constitutive equation can describe the flow stress behavior of Al2O3/Al composites, and the deformation activation energy and constitutive equations were calculated. The processing maps of Al2O3/Al-2 μm and Al2O3/Al-1 μm composites at strain of 0.6 were obtained and the optimum processing domains are in ranges of 300-330 °C, 0.007-0.03 s-1 and 335-360 °C, 0.015-0.06 s-1 for hot working, respectively. The instability zones of flow behavior can also be recognized by the maps. 展开更多
关键词 Al2O3/Al composites flake powder metallurgy flow stress processing map
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Dynamic recrystallization of Ti-6Al-2Zr-1Mo-1V in β forging process 被引量:2
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作者 欧阳德来 王克鲁 崔霞 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期761-767,共7页
The dynamic recrystallization(DRX) behavior of Ti-6Al-2Zr-1Mo-1V alloy was investigated at deformation temperature of 1000-1100 °C and strain rate of 10-3-1.0 s-1 by using compression test.The results show that... The dynamic recrystallization(DRX) behavior of Ti-6Al-2Zr-1Mo-1V alloy was investigated at deformation temperature of 1000-1100 °C and strain rate of 10-3-1.0 s-1 by using compression test.The results show that discontinuous dynamic recrystallization(DDRX) is the predominant recrystallization mechanism at temperature higher than 1050 °C and strain rate lower than 0.01 s-1.Meanwhile,continuous dynamic recrystallization is the main mechanism observed at temperature below 1050 °C and strain rate above 0.01 s-1,mixed with a few DDRX grains.In addition,decreasing strain rate and increasing deformation temperature are found to facilitate the progress of DRX and refinement of grains in the Ti alloy in β forging process. 展开更多
关键词 dynamic recrystallization Ti-6Al-2Zr-1Mo-1V alloy -forging process compression test
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Changes of the Transcriptional Levels of Molecules Associated with Endogenous Antigen Processing and Presentation in Porcine Skin-derived Dendritic Cells Infected with PCV2 in vivo 被引量:1
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作者 李建东 李焕荣 +2 位作者 聂晓华 遇奇 崔德凤 《Agricultural Science & Technology》 CAS 2012年第5期1089-1092,共4页
[Objective] This study aimed to investigate the changes of the transcriptional levels of molecules associated with endogenous antigen processing and presenta- tion in porcine skin-derived dendritic cells infected with... [Objective] This study aimed to investigate the changes of the transcriptional levels of molecules associated with endogenous antigen processing and presenta- tion in porcine skin-derived dendritic cells infected with PCV2 in vivo. [Method] Healthy 40-day-old Landrace piglets were infected with porcine circovirus type 2 (PCV2) and euthanized on the 34, 7rd, 14th, 21st and 35th d post inoculation (DPI). The porcine skin-derived dendritic cells (DCs) were collected to analyze the transcrip- tional levels of molecules (LMP7, UBP, MHC-I, calreticulin) associated with endogenous antigen processing and presentation by using real-time fluorescent quantitative PCR (real-time FQ-PCR). [Result] The results showed that the level of LMP7 mR- NAs was reduced significantly on the 3DPI (P〈0.05); the level of UBP mRNAs was consistently up-regulated, which increased significantly on the 21DPI and 35DPI (P〈 0.05); the level of MHC-I mRNAs was significantly down-regulated on the 7DPI (P〈 0.05); the level of calreticulin mRNAs was up-regulated slightly without significant dif- ference. [Conclusion] PCV2 can inhibit the endogenous antigen processing and presentation ability of porcine skin-derived DCs at early stages of infection. 展开更多
关键词 Porcine circovirus type 2 Skin-derived dendritic cells Endogenous antigen processing and presentation Real-time fluorescent quantitative PCR
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焦化废水中几种含氮杂环有机物在A_1-A_2-O系统中的降解特性研究 被引量:40
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作者 李咏梅 顾国雄 赵建夫 《环境科学学报》 CAS CSCD 北大核心 2002年第1期34-39,共6页
在对焦化废水中有机物在A1 A2 O生物膜系统中降解转化规律进行分析的基础上 ,选取焦化废水中 6种主要的含氮杂环化合物 :吡啶、吲哚、喹啉、异喹啉、2 甲基喹啉、8 羟基喹啉 ,与苯酚共同配制成溶液 ,在A1 A2 O生物膜系统中运行 ,结... 在对焦化废水中有机物在A1 A2 O生物膜系统中降解转化规律进行分析的基础上 ,选取焦化废水中 6种主要的含氮杂环化合物 :吡啶、吲哚、喹啉、异喹啉、2 甲基喹啉、8 羟基喹啉 ,与苯酚共同配制成溶液 ,在A1 A2 O生物膜系统中运行 ,结果表明上述几种含氮杂环有机物在A1 A2 O系统中都可得到较完全的去除 .它们在厌氧段的降解速率从大到小依次为 :吲哚>2 甲基喹啉 >8 羟基喹啉 >异喹啉 >喹啉 >吡啶 .在厌氧条件下 ,吲哚和喹啉存在拮抗作用 ,而吡啶对喹啉有协同作用 ; 展开更多
关键词 焦化废水 含氮杂环化合物 A1-a2-O生物膜系统 厌氧 废水处理 降解特性 有机物
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Influence of pretreatment process on structure, morphology and electrochemical properties of Li[Ni_(1/3)Co_(1/3)Mn_(1/3)]O_2 cathode material 被引量:1
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作者 杨顺毅 王先友 +3 位作者 刘子玲 陈权启 杨秀康 魏启亮 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期1995-2001,共7页
The layered Li[Ni1/3Mn1/3Co1/3]O2 was separately synthesized by pretreatment process of ball mill method and solution phase route, using [Ni1/3Co1/3Mn1/3]3O4 and lithium hydroxide as raw materials. The physical and el... The layered Li[Ni1/3Mn1/3Co1/3]O2 was separately synthesized by pretreatment process of ball mill method and solution phase route, using [Ni1/3Co1/3Mn1/3]3O4 and lithium hydroxide as raw materials. The physical and electrochemical behaviors of Li[Ni1/3Mn1/3Co1/3]O2 were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM) and electrochemical charge/discharge cycling tests. The results show that the difference in pretreatment process results in the difference in compound Li[Ni1/3Co1/3Mn1/3]O2 structure, morphology and the electrochemical characteristics. The Li[Ni1/3Mn1/3Co1/3]O2 prepared by solution phase route maintains the uniform spherical morphology of the [Ni1/3Co1/3Mn1/3]3O4, and it exhibits a higher capacity retention and better rate capability than that prepared by ball mill method. The initial discharge capacity of this sample reaches 178 mA-h/g and the capacity retention after 50 cycles is 98.7% at a current density of 20 mA/g. Moreover, it delivers high discharge capacity of 135 mA-h/g at a current density of 1 000 mA/g. 展开更多
关键词 lithium ion batteries Li[Ni1/3Co1/3Mn1/3]O2 carbonate co-precipitation method pretreatment process electrochemical characteristics
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