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活化双氧水漂白体系新技术的近况(一) 被引量:60
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作者 杨栋樑 王焕祥 《印染》 北大核心 2007年第2期44-48,共5页
在新开发的活化双氧水漂白体系技术中,过氧化合物的活化剂起关键作用。介绍了目前可供的几类活化剂,如烷酰基类、酰胺基类、N酰-基己内酰胺类、氧氮杂萘类和上述四种化合物混合物的性能及作用方式,以及在冷轧堆工艺中的效果,特别介绍了... 在新开发的活化双氧水漂白体系技术中,过氧化合物的活化剂起关键作用。介绍了目前可供的几类活化剂,如烷酰基类、酰胺基类、N酰-基己内酰胺类、氧氮杂萘类和上述四种化合物混合物的性能及作用方式,以及在冷轧堆工艺中的效果,特别介绍了日本新推出的用于棉冷轧堆工艺的过氧酸漂白系统OSBON。 展开更多
关键词 氧化漂白 过氧化氢 活化 冷轧堆法
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PNST脉冲中子全谱测井仪 被引量:21
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作者 郑华 董建华 刘宪伟 《测井技术》 CAS CSCD 北大核心 2011年第1期83-88,共6页
传统的碳氧比测井仪不测量地层泥质含量、孔隙度等参数,影响老井饱和度评价精度,为此研制了PNST脉冲中子全谱测井仪。通过合理的传感器结构设计和电路设计,PNST一次下井能同时完成双源距碳氧比、中子寿命、脉冲中子中子、能谱水流4... 传统的碳氧比测井仪不测量地层泥质含量、孔隙度等参数,影响老井饱和度评价精度,为此研制了PNST脉冲中子全谱测井仪。通过合理的传感器结构设计和电路设计,PNST一次下井能同时完成双源距碳氧比、中子寿命、脉冲中子中子、能谱水流4项测井功能,仪器自动化程度高;测井资料能提供岩性、泥质含量、孔隙度、饱和度、层位产水等解释信息,可以不依赖裸眼井测井资料进行套管井剩余油评价。在89个21%~31%孔隙度的砂岩地层将PNST解释结果与取心资料对比,有效孔隙度标准差为1.1%,剩余油饱和度标准差为4.5%。PNST适用于在套管井中寻找油气层、确定储层含油饱和度、监测油藏动态变化。 展开更多
关键词 脉冲中子全谱测井仪 碳氧比 中子寿命 氧活化 动态监测
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MZY-DD1脉冲中子氧活化测井仪 被引量:20
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作者 龚杰 李凤 《石油仪器》 2002年第2期24-26,62,共3页
脉冲中子氧活化测井是一种测量水流速度的测井方法。文章介绍MZY -DD1脉冲中子氧活化测井仪的工作原理、仪器结构及电路原理。仪器具有模块化设计及探头仅测量氧活化伽马射线的特点 ,流量测量范围和精度是 10m3 /d~ 6 0 0m3 /d和±... 脉冲中子氧活化测井是一种测量水流速度的测井方法。文章介绍MZY -DD1脉冲中子氧活化测井仪的工作原理、仪器结构及电路原理。仪器具有模块化设计及探头仅测量氧活化伽马射线的特点 ,流量测量范围和精度是 10m3 /d~ 6 0 0m3 /d和± 10 %。该仪器可用于注水、注聚井的注入剖面测井 ,还可用于注水、注聚井找窜、找漏。 展开更多
关键词 MZY-DD1脉冲中子氧活化测井仪 注入剖面测井 氧活化测井 脉冲中子 聚合物驱 油井
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PNST脉冲中子全谱测井仪在大庆油田的应用 被引量:19
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作者 郑华 刘宪伟 +2 位作者 董建华 沈付建 吕俊涛 《测井技术》 CAS CSCD 北大核心 2013年第5期541-546,551,共7页
PNST脉冲中子全谱测井仪用于套后地层参数评价,一次测井就能同时完成双源距碳氧比、中子寿命、脉冲中子-中子、能谱水流等测井功能。PNST测井仪在大庆油田已应用664井次,通常以70~120m/h速度测井,比传统DDCO-2双源距碳氧比测井... PNST脉冲中子全谱测井仪用于套后地层参数评价,一次测井就能同时完成双源距碳氧比、中子寿命、脉冲中子-中子、能谱水流等测井功能。PNST测井仪在大庆油田已应用664井次,通常以70~120m/h速度测井,比传统DDCO-2双源距碳氧比测井仪时效提高1倍以上,依据PNST测井资料增油降水措施有效率可达85%。PNST测井仪不仅能提供饱和度资料,而且具有套后独立评价储层的能力:通过叠合远俘获伽马计数FTMD曲线和热中子计数TCTSP曲线直观评价地层渗透性和划分储层;以地层俘获截面SGFM曲线计算地层泥质含量,以近远俘获伽马计数比RTMD曲线计算储层孔隙度;以中子寿命测井近伽马计数、远伽马计数及SGFM曲线对气层进行识别和定量解释;远氧活化指数IHM指示出水层位。PNST测井仪已全面替代了过去规模应用的DI)C02双源距碳氧比测井仪,成为大庆油田稳产的重要支撑技术。 展开更多
关键词 脉冲中子全谱测井仪 碳氧比 中子寿命 脉冲中子中子 氧活化 组合 应用
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氧气浓度与煤氧化特征关系的热重实验研究 被引量:18
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作者 朱红青 沈静 +2 位作者 王海燕 常明然 胡瑞丽 《煤矿安全》 CAS 北大核心 2014年第5期16-19,共4页
通过对朔州兴陶矿和长治常村矿2个煤样的热重实验,分别得到了2煤样升温速率为10K/min,氧浓度为5%、10%、15%、17%、21%、30%下的特征温度点,发现了煤样着火点随着氧浓度的增加逐渐降低。利用Coats-Redfen积分公式计算着火点温度至燃烧... 通过对朔州兴陶矿和长治常村矿2个煤样的热重实验,分别得到了2煤样升温速率为10K/min,氧浓度为5%、10%、15%、17%、21%、30%下的特征温度点,发现了煤样着火点随着氧浓度的增加逐渐降低。利用Coats-Redfen积分公式计算着火点温度至燃烧结束温度区段的活化能,结果表明:氧浓度增大,活化能呈增大趋势,兴陶矿煤样的活化能比常村矿煤样的活化能小,其更易发生自燃。同一煤样的TG曲线随着氧浓度的增加向左侧漂移,说明在一定范围内氧浓度的增加缩短了反应时间,煤样更易自燃。 展开更多
关键词 热重 TG曲线 氧浓度 活化能 煤自燃
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贫氧条件下煤自燃特性的热重-红外实验研究 被引量:15
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作者 邓军 杨俊义 +1 位作者 张玉涛 李亚清 《煤矿安全》 北大核心 2017年第4期24-28,共5页
为研究煤粉在贫氧条件下的自燃特性,利用TG/DSC-FTIR联用技术测试了顾北气煤在不同氧气浓度气氛下的燃烧放热过程,分析了贫氧条件下特征温度点、TG、DSC曲线的变化规律,通过红外光谱技术研究了CO、CO_2的释放规律,采用积分法计算了活性... 为研究煤粉在贫氧条件下的自燃特性,利用TG/DSC-FTIR联用技术测试了顾北气煤在不同氧气浓度气氛下的燃烧放热过程,分析了贫氧条件下特征温度点、TG、DSC曲线的变化规律,通过红外光谱技术研究了CO、CO_2的释放规律,采用积分法计算了活性温度点到着火点的活化能变化规律。研究表明:贫氧条件下,煤氧复合反应仍然能够持续,特征温度点在高温氧化阶段呈增大趋势,TG、DSC曲线向高温区偏移,CO、CO_2的峰值温度升高,增重阶段至燃烧阶段的活化能变化不大。 展开更多
关键词 贫氧 气煤 自燃特性 热重红外 活化能
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脉冲中子伽马综合测井 被引量:10
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作者 郑华 《大庆石油地质与开发》 CAS CSCD 北大核心 2007年第6期124-126,130,共4页
通过恰当地设计测井仪结构、中子发射时序以及能谱和时间谱采集方式,可以构成集碳氧比、中子寿命、氧活化3项功能于一体的脉冲中子伽马综合测井仪。与碳氧比测井仪相比,综合测井仪增加了实时测量地层热中子宏观俘获截面、近远探测器非... 通过恰当地设计测井仪结构、中子发射时序以及能谱和时间谱采集方式,可以构成集碳氧比、中子寿命、氧活化3项功能于一体的脉冲中子伽马综合测井仪。与碳氧比测井仪相比,综合测井仪增加了实时测量地层热中子宏观俘获截面、近远探测器非弹性散射及俘获伽马计数率比值、连续氧活化等功能,测井资料能在岩性、泥质含量、孔隙度、饱和度、层位产水等方面提供更丰富的实用信息。 展开更多
关键词 测井 脉冲中子 碳氧比 中子寿命 氧活化 组合 应用
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Hydrogen evolution activity enhancement by tuning the oxygen vacancies in self-supported mesoporous spinel oxide nanowire arrays 被引量:10
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作者 Dali Liu Chao Zhang +4 位作者 Yifu Yu Yanmei Shi Yu Yu Zhiqiang Niu Bin Zhang 《Nano Research》 SCIE EI CAS CSCD 2018年第2期603-613,共11页
The development of facile strategies to tune the oxygen vacancy (OV) content in transition metal oxides (TMOs) is paramount to obtain low-cost and stable electrocatalysts, but still highly challenging. Taking NiC0... The development of facile strategies to tune the oxygen vacancy (OV) content in transition metal oxides (TMOs) is paramount to obtain low-cost and stable electrocatalysts, but still highly challenging. Taking NiC0204 as a model system, we have experimentally established a facile calcination and electrochemical activation (EA) methodology to dramatically increase the concentration of OVs and provide theoretical insight into how the concentration of OVs affects the performance of spinel TMOs towards the electrochemical hydrogen evolution reaction (HER). A self-supported cathode of OV-rich NiC0204 nanowire arrays was found to exhibit higher HER activity and better stability in alkaline media than its counterparts with fewer OVs. The electrocatalytic HER activity was in good agreement with the increasing concentration of OVs in the studied samples. A large current density of 360 mA.cm-2 was reached with an overpotential of only 317 mV. Additionally, such a facile strategy was able to efficiently generate OVs in other TMOs (e.g., CoFe204 and NiFe204) for enhanced HER performance. In addition, our theoretical results suggest that the increasing OV concentration reduces the adsorption energy of water molecules and their dissociation energy barrier on the surface of the catalyst, thus leading to performance improvement of spinel TMOs toward the electrochemical HER. This work may open a new avenue to increase the concentration of OVs in TMOs in a controlled manner for promising applications in a variety of fields. 展开更多
关键词 electrochemical activation hydrogen evolutionreaction oxygen vacancy spinel phase thermal treatment
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Re-activation characteristics of preserved aerobic granular sludge 被引量:9
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作者 ZHANGLi-li ZHANGBo HUANGYu-feng CAIWei-min 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第4期655-658,共4页
In some industrial plants, wastewater was intermittently or seasonally generated. There may be periods during which wastewater treatment facilities have to be set into an idle phase over several weeks. When wastewater... In some industrial plants, wastewater was intermittently or seasonally generated. There may be periods during which wastewater treatment facilities have to be set into an idle phase over several weeks. When wastewater was generated again, the activated sludge flocs may have disintegrated. In this experiment, re-activation characteristics of aerobic granular sludge starved for 2 months were investigated. Specific oxygen utilization rate(SOUR) was used as an indicator to evaluate the metabolic activity of the sludge. The results revealed that aerobic granular sludge could be stored up to two months without running the risk of losing the integrity of the granules and metabolic potentials. The apparent color of aerobic granules stored at room temperature gradually turned from brownish-yellowish to gray brown. They appeared brownish-yellowish again 2 weeks after re-activation. The velocity and strength of granules after 2-month idle period could be fully restored about 3 weeks after re-activation. Metabolic activity, however, dropped to 15 8 mg O_2/(g MLVSS·h), i.e. 74 % reduction after 2 months of storage. After restarting the reactor, it took 2 weeks that SOUR of up to 48 5 mg O_2 /(g MLVSS·h) was achieved. A stable effluent COD concentration of less than 150 mg/L was achieved during the re-activation process. 展开更多
关键词 aerobic granular sludge re-activation characteristics SBR specific oxygen consumption rate
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氧浓度对煤低温氧化热效应影响规律研究 被引量:8
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作者 陈龙 张嬿妮 《中国安全生产科学技术》 CAS CSCD 北大核心 2020年第6期49-54,共6页
为了准确掌握氧浓度对煤低温氧化热效应的影响,采用C80微量量热仪研究低温阶段煤氧化的自热过程,根据单升温速率的非等温动力学分析方法,得到不同氧浓度下煤样的活化能。研究结果表明:氧浓度对实验初始阶段的热流曲线和放热量的影响较小... 为了准确掌握氧浓度对煤低温氧化热效应的影响,采用C80微量量热仪研究低温阶段煤氧化的自热过程,根据单升温速率的非等温动力学分析方法,得到不同氧浓度下煤样的活化能。研究结果表明:氧浓度对实验初始阶段的热流曲线和放热量的影响较小,随着温度的升高,氧浓度对热流曲线和放热量影响逐渐变得明显,放热趋势随着氧浓度的增大而增强;煤样的初始放热温度随着氧浓度的增大而降低;活化能随着氧气浓度的降低呈阶梯式上升;总放热量和氧浓度服从线性方程y=ax+b;与21%(空气气氛)氧浓度相比,15%,10%和5%氧浓度下煤的放热量分别降低了约19%,33%和46%,表明降低氧浓度对煤样的氧化放热具有明显的减缓作用。因此可以加强采空区的密闭性检测、注入惰性气体,使采空区的氧浓度尽可能地低,对采空区煤自热升温的防治有着理论指导意义。 展开更多
关键词 氧浓度 低温氧化 热效应 煤自燃 活化能
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脉冲中子氧活化能谱测井在江苏油田的应用 被引量:8
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作者 陈刚 《石油仪器》 2006年第6期59-61,64,共4页
文章介绍了脉冲中子氧活化能谱测井的测量原理、测井工艺及该技术在江苏油田应用情况。分析了江苏油田的15口脉冲中子氧活化测井资料在定量确定井内介质为水、聚合物的笼统井(正注、上返)、配注井的各层吸液状况;确定配注井内封隔器、... 文章介绍了脉冲中子氧活化能谱测井的测量原理、测井工艺及该技术在江苏油田应用情况。分析了江苏油田的15口脉冲中子氧活化测井资料在定量确定井内介质为水、聚合物的笼统井(正注、上返)、配注井的各层吸液状况;确定配注井内封隔器、配水器等工具的工作状态;确定管外窜槽;检查封堵效果四方面的应用效果。通过15口井的应用可知,该技术不仅能够定量确定笼统注入井内介质(水或聚合物)的各层吸液状况,同时在江苏油田能够解决传统注入剖面测井方法存在的技术问题。 展开更多
关键词 氧活化 测井 吸入剖面
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氧活化、示踪相关测井在低压井找漏找窜中的应用 被引量:8
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作者 王连波 《石油管材与仪器》 2020年第1期89-93,共5页
低压注水会造成油田注水系统紊乱,影响油田产量,而油套管窜漏是造成水井低压的主要原因。首先制定了低压井找窜漏的测试方案,方案主要运用了脉冲中子氧活化和示踪相关测井结合的方法,同时辅以同位素五参数、PI90、分层压力等测试工艺。... 低压注水会造成油田注水系统紊乱,影响油田产量,而油套管窜漏是造成水井低压的主要原因。首先制定了低压井找窜漏的测试方案,方案主要运用了脉冲中子氧活化和示踪相关测井结合的方法,同时辅以同位素五参数、PI90、分层压力等测试工艺。按照制定的施工方案,氧活化测井负责查清管内水流情况,示踪相关测井开展管外水流查找,辅以其它测试方法进行验证、调查,开展了窜漏的查找,三口井取得了较好的效果,准确查找到了窜漏点。应用脉冲中子氧活化进行找漏测试时,在施工过程中随时调整水井的正反注状态,更便于漏点的查找,同时尝试开拓了示踪相关测井寻找管外窜流这一新领域。 展开更多
关键词 氧活化 示踪相关 低压 找漏 反注
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Promotion effects of nickel-doped Al2O3-nanosheet-supported Au catalysts for CO oxidation 被引量:8
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作者 Rao Lu Lei He +2 位作者 Yang Wang Xin-Qian Gao Wen-Cui Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第2期350-356,共7页
Supported gold catalysts show high activity toward CO oxidation, and the nature of the support significantly affects the catalytic activity. Herein, serial Ni doping of thin porous Al2 O3 nanosheets was performed via ... Supported gold catalysts show high activity toward CO oxidation, and the nature of the support significantly affects the catalytic activity. Herein, serial Ni doping of thin porous Al2 O3 nanosheets was performed via a precipitation-hydrothermal method by varying the amount of Ni during the precipitation step. The prepared nanosheets were subsequently used as supports for the deposition of Au nanoparticles(NPs). The obtained Au/Nix Al catalysts were studied in the context of CO oxidation to determine the effect of Ni doping on the supports. Enhanced catalytic performances were obtained for the Au/Nix Al catalysts compared with those of the Au supported on bare Al2 O3. The Ni content and pretreatment atmosphere were both shown to influence the catalytic activity. Pretreatment under a reducing atmosphere was beneficial for improving catalytic activity. The highest activity was observed for the catalysts with a Ni/Al molar ratio of 0.05, achieving complete CO conversion at 20 °C with a gold loading of 1 wt%. The in-situ FTIR results showed that the introduction of Ni strengthened CO adsorption on the Au NPs. The H2-TPR and O2-TPD results indicated that the introduction of Ni produced new oxygen vacancies and allowed the oxygen molecules to be adsorbed and activated more easily. The improved catalytic performance after doping Ni was attributed to the smaller size of the Au NPs and more active oxygen species. 展开更多
关键词 ALUMINA Gold catalyst Nickel doping CO oxidation oxygen activation
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脉冲中子水流测井技术及其应用 被引量:7
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作者 任建华 《油气地质与采收率》 CAS CSCD 北大核心 2006年第3期91-93,共3页
油田开发进入中、后期时,搞好注入井的测试调剖和加大注入井的管理在开发调整中的作用越来越重要。脉冲中子水流测井是一种测量水流速度的测井技术,其利用脉冲中子与氧元素相互作用后能放射出特征伽马射线,通过检测伽马射线来确定仪器... 油田开发进入中、后期时,搞好注入井的测试调剖和加大注入井的管理在开发调整中的作用越来越重要。脉冲中子水流测井是一种测量水流速度的测井技术,其利用脉冲中子与氧元素相互作用后能放射出特征伽马射线,通过检测伽马射线来确定仪器周围含氧流体的流动情况。该技术可以穿透油管和套管进行测试,且不受流体流动方向、管内或管外流动的限制;还可实现对配注井内的管柱工具是否堵死、泄漏以及管外窜流的检测。 展开更多
关键词 脉冲中子 氧活化 注入剖面 管外窜流
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Selective photocatalytic oxidation of methane to C1 oxygenates by regulating sizes and facets over Au/ZnO 被引量:1
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作者 Qiang Zhou Xinyu Wang +6 位作者 Xiaojie Tan Qinhua Zhang Hao Yang Tao Xing Mingqing Wang Mingbo Wu Wenting Wu 《Nano Research》 SCIE EI CSCD 2024年第5期3810-3818,共9页
Photocatalytic oxidation of methane to value-added chemicals is a promising process under mild conditions,nevertheless confronting great challenges in efficiently activating C-H bonds and inhibiting over-oxidation.Her... Photocatalytic oxidation of methane to value-added chemicals is a promising process under mild conditions,nevertheless confronting great challenges in efficiently activating C-H bonds and inhibiting over-oxidation.Herein,we propose a comprehensive strategy for the selective generation of reactive oxygen species(ROS)by regulating the sizes and facets of Au nanoparticles loaded on ZnO.For photocatalytic methane oxidation at ambient temperature,a high oxygenates yield of 36.4 mmol·g^(-1)·h^(-1) with a nearly 100%selectivity has been achieved over the optimized 1.0%Au/ZnO-9.6(1%Au with(111)facet and 9.6 nm size on ZnO)photocatalyst,exceeding most reported literatures.Mechanism investigations reveal that 1.0%Au/ZnO-9.6 with the medium size and Au(111)facet guarantees the favourable formation of superoxide radicals(·OOH)through mild oxygen reduction,ultimately leading to excellent photocatalytic methane oxidation performance.This work provides some guidance for the delicate design of photocatalysts for efficient photocatalytic methane oxidation and oxygen utilization. 展开更多
关键词 photocatalysis methane oxidation radical regulation oxygen activation NANOMATERIAL
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Oxygen-defects evolution to stimulate continuous capacity increase in Co-free Li-rich layered oxides 被引量:2
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作者 Yibin Zhang Xiaohui Wen +3 位作者 Zhepu Shi Bao Qiu Guoxin Chen Zhaoping Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期259-267,I0006,共10页
Though oxygen defects are associated with deteriorated structures and aggravated cycling performance in traditional layered cathodes,the role of oxygen defects is still ambiguous in Li-rich layered oxides due to the i... Though oxygen defects are associated with deteriorated structures and aggravated cycling performance in traditional layered cathodes,the role of oxygen defects is still ambiguous in Li-rich layered oxides due to the involvement of oxygen redox.Herein,a Co-free Li-rich layered oxide Li_(1.286)Ni_(0.071)Mn_(0.643)O_(2)has been prepared by a co-precipitation method to systematically investigate the undefined effects of the oxygen defects.A significant O_(2)release and the propagation of oxygen vacancies were detected by operando differential electrochemical mass spectroscopy(DEMS)and electron energy loss spectroscopy(EELS),respectively.Scanning transmission electron microscopy-high angle annular dark field(STEMHAADF)reveals the oxygen vacancies fusing to nanovoids and monitors a stepwise electrochemical activation process of the large Li_(2)MnO_(3)domain upon cycling.Combined with the quantitative analysis conducted by the energy dispersive spectrometer(EDS),existed nano-scale oxygen defects actually expose more surface to the electrolyte for facilitating the electrochemical activation and subsequently increasing available capacity.Overall,this work persuasively elucidates the function of oxygen defects on oxygen redox in Co-free Li-rich layered oxides. 展开更多
关键词 Li-rich layered oxide Irreversible oxygen loss Nano-scale oxygen defect Li_(2)MnO_(3)-domain activation
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Atomic-level unveiling secondary recrystallization enabled microand macroscopic polarization enhancement for piezophotocatalytic oxygen activation
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作者 Kai Lin Zijian Zhu +2 位作者 Weiyi Ge Tianxing Jiang Hongwei Huang 《Nano Research》 SCIE EI CSCD 2024年第6期5040-5049,共10页
Piezoelectric semiconductors bear the bifunctional photocatalysis and piezocatalysis,while the absent or weak internal charge driving force severely restricts its catalytic activity.Developing polarization strategy is... Piezoelectric semiconductors bear the bifunctional photocatalysis and piezocatalysis,while the absent or weak internal charge driving force severely restricts its catalytic activity.Developing polarization strategy is desirable,and particularly understanding its mechanism from a microscopic perspective remains scanty.Herein,we report a secondary recrystallization approach to achieving the simultaneous micro-and macroscopic polarization enhancement on Bi2WO6 nanosheets for boosting piezo-photocatalytic oxygen activation,and unravel the mechanism at an atom-level.The secondary recrystallization process not only results in a strengthened distortion of[WO6]octahedra with distortion index enhancement by~20%for a single octahedron,but also enables lateral crystal growth of nanosheets along the ab plane(av.50 to 180 nm),which separately allows the rise in dipole moment of unit cell(e.g.,1.63 D increase along a axis)and the stacking of the distorted[WO6]octahedron to accumulate the unit cell dipole,collectively contributing to the considerably strengthened spontaneous polarization and piezoelectricity.Besides,exposure of large-area{001}front facet enables more efficient capture and conversion of stress into piezo-potential.Therefore,the well-recrystallized Bi2WO6 nanosheets exhibit considerably promoted piezo-photocatalytic reactive oxygen species generation,given the decreased specific surface area.This work presents a feasible methodology to regulate inside-out polarization for guiding carriers transfer behavior,and may advance the solid understanding on the intrinsic mechanism. 展开更多
关键词 secondary recrystallization piezo-photocatalytic oxygen activation octahedron distortion polar units stacking micro-and macroscopic polarization enhancement
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Unravelling the nature of the active species as well as the Mn doping effect over gamma-Al_(2)O_(3) catalyst for eliminating AsH_(3) and PH_(3)
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作者 Bowen Xu Jiaxin Qu +6 位作者 Xueqian Wang Langlang Wang Yu Pu Ping Ning Yibing Xie Yixing Ma Qiang Ma 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第2期213-225,共13页
To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by CuO-Al_(2)O_(3)in a reducing atmosphere under micro-oxygen conditions,Cu-Mn modifiedγ-Al_(2)O_(3... To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by CuO-Al_(2)O_(3)in a reducing atmosphere under micro-oxygen conditions,Cu-Mn modifiedγ-Al_(2)O_(3)catalysts were prepared.The characteristics of the catalysts showed that Mn reduced the crystallinity of the active CuO component,increased the number of oxygen vacancies and acidic sites on the catalyst surface,enhanced the mobility of surface oxygen,and the interaction between copper and manganese promoted the redox cycling ability of the catalysts and improved their oxidation performance,which increased the conversion frequency(TOF)by 2.54×10^(-2)to 3.07×10^(-2)sec^(-1).On the other hand,the introduction of Mn reduced the production of phosphate and As_(2)O_(3)on the catalyst surface by30.96%and 44.9%,which reduced the coverage and inerting of the active sites by phosphate and As_(2)O_(3),resulting in an 8 hr(6 hr)improvement in the stability of PH_(3)(AsH_(3))removal. 展开更多
关键词 AsH_(3)-PH_(3)removal oxygen activation Mn doping Stability enhancement
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Breakthrough of Carbon-Ash Recalcitrance in Hydrochar via Molten Carbonate:Engineering Mineral-Rich Biowaste Toward Sustainable Platform Carbon Materials
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作者 Zihan Wang Leli Zhang +1 位作者 Yuanhui Zhang Zhidan Liu 《Engineering》 SCIE EI CAS CSCD 2024年第5期167-177,共11页
The function-led design of porous hydrochar from mineral-rich biowaste for environmental applications inevitably suffers from carbon-ash recalcitrance.However,a method to alter the original carbon skeleton with ash re... The function-led design of porous hydrochar from mineral-rich biowaste for environmental applications inevitably suffers from carbon-ash recalcitrance.However,a method to alter the original carbon skeleton with ash remains elusive and hinders the availability of hydrochar.Herein,we propose a facile strategy for breaking the rigid structure of carbon-ash coupled hydrochar using phase-tunable molten carbonates.A case system was designed in which livestock manure and NaHCO3 were used to prepare the activated hydrochar,and NH3 served as the target contaminant.Due to the redox effect,we found that organic fractions significantly advanced the melting temperature of Na2CO3 below 800℃.The Na species steadily broke the carbon-ash interaction as the thermal intensity increased and transformed inorganic constituents to facilitate ash dissolution,rebuilding the hydrochar skeleton with abundant hierarchical channels and active defect edges.The surface polarity and mesopore distribution collectively governed the five cycles NH3 adsorption attenuation process.Manure hydrochar delivered favorable potential for application with a maximum overall adsorption capacity of 100.49 mg·g^(-1).Integrated spectroscopic characterization and theoretical computations revealed that incorporating NH3 on the carbon surface could transfer electrons to chemisorbed oxygen,which promoted the oxidation of pyridine-N during adsorption.This work offers deep insight into the structure function correlation of hydrochar and inspires a more rational design of engineered hydrochar from high-ash biowaste. 展开更多
关键词 Hydrochar Livestock manure Ammonia adsorption DEASHING oxygen activation
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Synthesizing active and durable cubic ceria catalysts(<6 nm)for fast dehydrogenation of bio-polyols to carboxylic acids coproducing green H_(2)
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作者 Mengyuan Liu Puhua Sun +3 位作者 Guangyu Zhang Xin Jin Chaohe Yang Honghong Shan 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期529-543,共15页
Dehydrogenation is considered as one of the most important industrial applications for renewable energy.Cubic ceria-based catalysts are known to display promising dehydrogenation performances in this area.Large partic... Dehydrogenation is considered as one of the most important industrial applications for renewable energy.Cubic ceria-based catalysts are known to display promising dehydrogenation performances in this area.Large particle size(>20 nm)and less surface defects,however,hinder further application of ceria materials.Herein,an alternative strategy involving lactic acid(LA)assisted hydrothermal method was developed to synthesize active,selective and durable cubic ceria of<6 nm for dehydrogenation reactions.Detailed studies of growth mechanism revealed that,the carboxyl and hydroxyl groups in LA molecule synergistically manipulate the morphological evolution of ceria precursors.Carboxyl groups determine the cubic shape and particle size,while hydroxyl groups promote compositional transformation of ceria precursors into CeO_(2) phases.Moreover,enhanced oxygen vacancies(Vo)on the surface of CeO_(2) were obtained owing to continuous removal of O species under reductive atmosphere.Cubic CeO_(2) catalysts synthesized by the LA-assisted method,immobilized with bimetallic PtCo clusters,exhibit a record high activity(TOF:29,241 h^(-1))and Vo-dependent synergism for dehydrogenation of bio-derived polyols at 200℃.We also found that quenching Vo defects at air atmosphere causes activity loss of PtCo/CeO_(2) catalysts.To regenerate Vo defects,a simple strategy was developed by irradiating deactivated catalysts using hernia lamp.The outcome of this work will provide new insights into manufacturing durable catalyst materials for aqueous phase dehydrogenation applications. 展开更多
关键词 Cubic ceria oxygen vacancy DEHYDROGENATION C-H bond activation
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