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Mg-doped SrTaO_(2)N as a visible-light-driven H_(2)-evolution photocatalyst for accelerated Z-scheme overall water splitting
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作者 Jun Xu Ying Luo +4 位作者 Qiaoqi Guo Wenzheng Sun Shanshan Chen Zheng Wang Hong He 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期70-78,共9页
Perovskite SrTaO_(2)N is one of the most promising narrow-bandgap photocatalysts for Z-scheme overall water splitting.However,the formation of defect states during thermal nitridation severely hinders the separation o... Perovskite SrTaO_(2)N is one of the most promising narrow-bandgap photocatalysts for Z-scheme overall water splitting.However,the formation of defect states during thermal nitridation severely hinders the separation of charges,resulting in poor photocatalytic activity.In the present study,we successfully synthesize SrTaO_(2)N photocatalyst with low density of defect states,uniform morphology and particle size by flux-assisted one-pot nitridation combined with Mg doping.Some important parameters,such as the size of unit cell,the content of nitrogen,and microstructure,prove the successful doping of Mg.The defect-related carrier recombination has been significantly reduced by Mg doping,which effectively promotes the charge separation.Moreover,Mg doping induces a change of the band edge,which makes proton reduction have a stronger driving force.After modifying with the core/shell-structured Pt/Cr_(2)O_(3)cocatalyst,the H_(2)evolution activity of the optimized SrTaO_(2)N:Mg is 10 times that of the undoped SrTaO_(2)N,with an impressive apparent quantum yield of 1.51%at 420 nm.By coupling with Au-FeCoO_(x)modified BiVO_(4)as an O_(2)-evolution photocatalyst and[Fe(CN)_(6)]_(3)−/[Fe(CN)_(6)]_(4)−as the redox couple,a redox-based Z-scheme overall water splitting system is successfully constructed with an apparent quantum yield of 1.36%at 420 nm.This work provides an alternative way to prepare oxynitride semiconductors with reduced defects to promote the conversion of solar energy. 展开更多
关键词 Photocatalytic overall water splitting SrTaO_(2)n photocatalyst Mg doping Defect density COCATALYST
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含改性氯化合物对N2/细水雾抑制LPG爆炸影响研究
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作者 裴蓓 胡紫维 +3 位作者 韩谕良 徐梦娇 陈立伟 邵翔宇 《爆炸与冲击》 EI CAS CSCD 北大核心 2024年第11期169-180,共12页
为了提高对液化石油气(liquefied petroleum gas,LPG)的抑爆效能,采用自主设计的半开式有机玻璃管道搭建了N2/细水雾抑爆实验平台,从爆炸超压、火焰传播速度及其峰值来临时间、火焰结构等4个方面分析含改性氯化合物N2/细水雾抑爆效果。... 为了提高对液化石油气(liquefied petroleum gas,LPG)的抑爆效能,采用自主设计的半开式有机玻璃管道搭建了N2/细水雾抑爆实验平台,从爆炸超压、火焰传播速度及其峰值来临时间、火焰结构等4个方面分析含改性氯化合物N2/细水雾抑爆效果。结果表明:含氯化合物对表面活性剂具有选择性,KCl、NaCl和NH4Cl与脂肪醇聚氧乙烯醚(AeO9)、有机硅表面活性剂(Sicare2235)等2种表面活性剂之间的协同增效效果更优,爆炸超压峰值、火焰传播速度峰值均明显降低,且峰值来临时间明显延长;十二烷基硫酸钠(sodium dodecyl sulfate,SDS)仅与NaCl共同作用时抑爆效果有明显提升,与其他3种氯盐共同作用时没有增效效果甚至产生促爆现象;FeCl2与表面活性剂协同时会出现爆炸增强现象;含氯化合物与表面活性剂共同作用时,复合溶液的表面张力存在最佳值,即表面张力在20 mN/m时,抑爆效能最佳。化学动力学数值模拟结果表明:含改性氯化合物N2/细水雾能够有效降低绝热火焰温度,消耗关键自由基,中断燃烧链式反应,其抑爆的协同增效机理主要体现在N2惰化稀释、表面活性剂调控水雾粒径增加冷却效应和抑制链式反应3个方面。 展开更多
关键词 LPG爆炸抑制 n2/细水雾 含氯化合物 表面活性剂
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养殖水体NO_(2)^(-)-N降解复合菌剂制备及特性研究
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作者 伍俊溢 魏祥东 《现代畜牧科技》 2024年第6期20-24,共5页
随着我国水产养殖规模也逐年上升,养殖水体中氮化合物累积问题日益严重。为实现我国水产行业的安全生产,本文筛选出一种NO_(2)^(-)-N降解菌,并与光合菌、乳酸菌进行复配以此制备复合菌剂。通过单因素试验分析温度、pH值、亚硝酸盐初始... 随着我国水产养殖规模也逐年上升,养殖水体中氮化合物累积问题日益严重。为实现我国水产行业的安全生产,本文筛选出一种NO_(2)^(-)-N降解菌,并与光合菌、乳酸菌进行复配以此制备复合菌剂。通过单因素试验分析温度、pH值、亚硝酸盐初始浓度、菌种接种量等对NO_(2)^(-)-N降解的影响,确定不同影响因素下复合菌剂的最佳降解效果和生长状态。研究结果表明,从活性淤泥中筛选带1株具有高效NO_(2)^(-)-N氧化性质的菌株A3,并与光合细菌(Rhodopseudomonas palustris)、乳酸菌(Lactobacillus acidophilus)按照32∶2∶1混合,该比例降解效率最高。复合菌剂在40℃,pH值为9.0、pH值为6.0的条件下,OD600值稳定在0.2~0.4,对NO_(2)^(-)-N的降解率保持在50%左右。复合菌剂在25℃,pH值为7.5的条件下长势最好,降解率最高;复合菌剂的降解率随初始NO_(2)^(-)-N浓度的升高而降低,OD600值变化不明显,表明复合菌剂与A3菌株对NO_(2)^(-)-N有很强的耐受性,能够在0.1~8.0 g/L的条件下维持降解活性,保持一定的降解速率。 展开更多
关键词 复合微生物菌剂 nO_(2)^(-)-n 养殖水体 nO_(2)^(-)-n高效氧化菌
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Suppression of methane/air explosion by water mist with potassium halide additives driven by CO2 被引量:4
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作者 Wei Tan Dong Lü +2 位作者 Liyan Liu Guorui Zhu Nan Jiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第11期2742-2748,共7页
To enhance the explosion suppression effects of water mist, various potassium halide additives were tested in a confined vessel filled with a 10% mixture of methane/air. Air and CO2(0.7 MPa) were used as driver gases.... To enhance the explosion suppression effects of water mist, various potassium halide additives were tested in a confined vessel filled with a 10% mixture of methane/air. Air and CO2(0.7 MPa) were used as driver gases. The results revealed that halide additives exhibit considerable suppression effects on explosion overpressure. A30% KI mist decreased the explosion overpressure by 27.46% compared with the suppression by pure water mist under the same conditions. When CO2 is used as the driver gas, it will dissolve in water under high pressure.The synergistic effect of a CO2 solution with an effective additive afforded significant suppression. Under the same conditions, the overpressures suppressed by a mist of 30% KI + 0.7 MPa CO2 solution decreased by 33.53% compared with those suppressed by pure water mist driven by air. The synergistic suppression effect is much better than that of a 0.7 MPa CO2 solution mist or 30% KI mist alone. The multicomponent additives can be considered when suppressing methane/air explosions with pressure-formed water mist. 展开更多
关键词 METHAnE Explosion SUPPRESSIOn water mist HALIDE CO2
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p-n型NiWO_(4)/ZnIn_(2)S_(4)异质结光解水析氢性能
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作者 闫爱华 高埜 +4 位作者 张晓辉 黄飞 张同洋 张吉旭 赵文学 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2023年第12期74-83,共10页
采用水热/水浴两步法构筑了p-n型NiWO_(4)(NWO)/ZnIn_(2)S_(4)(ZIS)异质结,研究了不同含量的NWO对ZIS物相组分、形貌结构、能带结构、光谱吸收及光解水析氢性能等的影响,并采用一系列表征手段探讨了NWO/ZIS异质结的光催化机理.结果表明... 采用水热/水浴两步法构筑了p-n型NiWO_(4)(NWO)/ZnIn_(2)S_(4)(ZIS)异质结,研究了不同含量的NWO对ZIS物相组分、形貌结构、能带结构、光谱吸收及光解水析氢性能等的影响,并采用一系列表征手段探讨了NWO/ZIS异质结的光催化机理.结果表明,负载NWO后,ZIS物相组分及形貌结构未发生显著变化,两种材料界面接触紧密且分布均匀;在可见光辐照下,NWO/ZIS异质结光解水析氢性能得到了显著提升,其中,最佳样品NWO-35/ZIS析氢速率达到5204.8μmol·g^(-1)·h^(-1),为纯相ZIS(1566.4μmol·g^(-1)·h^(-1))的3.32倍;循环实验结果表明,NWO/ZIS样品具有很好的光稳定性;能带结构和光电子动力学表征结果证实了p-n型异质结内建电场驱动的光生载流子的传输机制. 展开更多
关键词 ZnIn_(2)S_(4) niWO_(4) p-n型异质结 内建电场 光解水析氢
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Effect of water stress on N_2O emission rate of 5 tree species
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作者 王淼 李秋荣 +1 位作者 肖冬梅 王长科 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第1期19-23,J001,共6页
The N2O emission rates, photosynthesis, respiration and stomatal conductance of the dominant tree species from broadleaf/Korean pine forest in Changbai Mountain were measured by simulated water stress with the closed ... The N2O emission rates, photosynthesis, respiration and stomatal conductance of the dominant tree species from broadleaf/Korean pine forest in Changbai Mountain were measured by simulated water stress with the closed bag-gas chromatography. A total of five species seedlings were involved in this study, i.e.,Pinus koraiensis Sieb. et Zucc,Fraxinus mandshurica Rupr,Juglans mandshurica Maxim,Tilia amurensis Rupr, andQuercus mongolica Fisch. ex Turcz.. The results showed that the stomatal conductance, net photosynthetic rate and N2O emission of leaves were significantly reduced under the water stress. The stoma in the leaves of trees is the main pathway of N2O emission. N2O emission in the trees mainly occurred during daytime. N2O emission rates were different in various tree specie seedlings at the same water status. In the same tree species, N2O emission rates decreased as the reduction of soil water contents. At different soil water contents (MW, LW) the N2O emission rates ofPinus koraiensis decreased by 34.43% and 100.6% of those in normal water condition, respectively. In broadleaf arbor decreased by 31.93% and 86.35%, respectively. Under different water stresses N2O emission rates in five tree species such asPinus koraiensis, Fraxinus mandshurica, Juglans mandshurica, Tilia amurensis, andQuercus mongolica were 38.22, 14.44, 33.02, 16.48 and 32.33 ngN2O·g?1DW·h?1, respectively. Keywords Trees - N2O emission rate - Soil water stress - broadleaf/Korean pine forest - Changbai Mountain CLC number S718.55 Document code A Foundation item: This project was supported by the National Natural Science Foundation of China (No. 30271068), the grant of the Knowledge Innovation Program of Chinese Academy of Sciences (KZ-CX-SW-01-01B-10), and the Special Funds for Major State Basic Research Program of China (No. G1999043407)Biography: Wang Miao (1964-), male, associate professor in Institute of Applied Ecology, Chinese Academy of Science, Shenyang 110016, P. R. China.Responsible editor: Song Funan 展开更多
关键词 Trees n2O emission rate Soil water stress broadleaf/Korean pine forest Changbai Mountain
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Ⅱ型C_(2)N/ZnO异质结水分解光催化剂的第一性原理研究
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作者 陈晶亮 栾丽君 +7 位作者 张茹 张研 杨云 刘剑 田野 魏星 樊继斌 段理 《材料导报》 CSCD 北大核心 2023年第11期25-32,共8页
基于单层C_(2)N和ZnO,构建了一种新型2D范德华(vdW)异质结。在第一性原理下进行密度泛函理论计算,系统地研究了C_(2)N/ZnO异质结的光催化应用。结果表明,C_(2)N/ZnO异质结具有1.68 eV的直接带隙,其Ⅱ型带对准可以促使光生电子和空穴分... 基于单层C_(2)N和ZnO,构建了一种新型2D范德华(vdW)异质结。在第一性原理下进行密度泛函理论计算,系统地研究了C_(2)N/ZnO异质结的光催化应用。结果表明,C_(2)N/ZnO异质结具有1.68 eV的直接带隙,其Ⅱ型带对准可以促使光生电子和空穴分离在不同层上。由Mulliken电荷布局分析可知,C_(2)N层有0.53个电子转移到ZnO层,在异质结界面处形成了一个较强的内建电场E int,抑制了光生电子空穴对的复合。此外,C_(2)N/ZnO异质结的带边位置跨过了pH=2~7时的水氧化还原电位,同时拉伸应变可以增大其光催化水分解pH范围。特别地,C_(2)N/ZnO异质结保留了高载流子迁移率和优异的光吸收性能,太阳能-氢能(STH)转换效率可达到24.6%。因此,C_(2)N/ZnO异质结是一种具有应用前景的水分解光催化剂。 展开更多
关键词 C_(2)n/ZnO异质结 水分解 第一性原理 光催化
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采用生物净化滤柱同步降低COD_(Mn)并去除NH^(+)-N、Mn^(2+)的启动过程研究
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作者 梁雄伟 程修文 +1 位作者 于少鹏 孟博 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第2期265-270,共6页
采用生物净化滤柱降低微污染水源水中的COD_(Mn)并去除NH-N、Mn^(2+),考察净化启动过程中以及沿程的CODMn、P(NH_(4)^(+)-N)、p(Mn^(2+))变化.结果表明,在71d时,出水中的CODMnp(NH_(4)^(+)-N)、p(Mn^(2+))均低于《生活饮用水卫生标准》(... 采用生物净化滤柱降低微污染水源水中的COD_(Mn)并去除NH-N、Mn^(2+),考察净化启动过程中以及沿程的CODMn、P(NH_(4)^(+)-N)、p(Mn^(2+))变化.结果表明,在71d时,出水中的CODMnp(NH_(4)^(+)-N)、p(Mn^(2+))均低于《生活饮用水卫生标准》(GB5749-2006),并且COD_(Mn)最先达标,生物除锰效果受到NH_(4)^(+)-N氧化过程中产生的NO,-N的影响.净化的沿程分析结果表明,随着净化启动的进行,CODMm的降低率和NHt-N的去除率逐渐提高,稳定阶段CODMn、NH_(4)^(+)-N主要在0~0.4m段去除.净化启动初期Mn的去除主要依靠锰砂的吸附,当吸附饱和后,出水处p(Mn^(2+))逐渐升高;当NO,-N被全部氧化后,Mn的去除率快速提高;稳定阶段,Mn^(2+)主要在0~0.4m段去除。 展开更多
关键词 COD_(Mn) nH_(4)^(+)-n Mn^(2+) 生物净化滤柱 微污染水源水
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Effects of Temperature and Water Saturation on CO_2 Production and Nitrogen Mineralization in Alpine Wetland Soils 被引量:14
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作者 GAO Jun-Qin OUYANG Hua +2 位作者 XU Xing-Liang ZHOU Cai-Ping ZHANG Feng 《Pedosphere》 SCIE CAS CSCD 2009年第1期71-77,共7页
Relationships between carbon (C) production and nitrogen (N) mineralization were investigated in two alpine wetland soils of the Tibetan Plateau using laboratory incubation under different temperatures (5, 15, 25, and... Relationships between carbon (C) production and nitrogen (N) mineralization were investigated in two alpine wetland soils of the Tibetan Plateau using laboratory incubation under different temperatures (5, 15, 25, and 35 ℃) and water saturation (noninundation and inundation). A significant positive relationship was found between CO2 production and N mineralization under increasing temperatures from 5 to 35 ℃ with the same water saturation condition in the marsh soil (r2 > 0.49, P < 0.0001) and the peat soil (r2 > 0.38, P < 0.002), and a negative relationship with water saturation increasing at the same temperature, especially 25 and 35 ℃, in the marsh soil (r2 > 0.70, P < 0.009) and the peat soil (r2 > 0.61, P < 0.013). In conclusion, temperatures and water saturation could regulate the relationship between CO2 production and net N mineralization in the Tibetan alpine marsh and peat soils. 展开更多
关键词 CO2 production n mineralization TEMPERATURE water saturation WETLAnD
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Efficient Photoelectrochemical Water Splitting by g-C_3N_4/TiO_2 Nanotube Array Heterostructures 被引量:7
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作者 Changhai Liu Fang Wang +4 位作者 Jin Zhang Ke Wang Yangyang Qiu Qian Liang Zhidong Chen 《Nano-Micro Letters》 SCIE EI CAS 2018年第2期247-259,共13页
Well-ordered TiO_2 nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_3N_4) were fabricated by anodic oxidization and calcination process.First, TNTAs were prepared via the anodic oxidation of Ti foil i... Well-ordered TiO_2 nanotube arrays(TNTAs)decorated with graphitic carbon nitride(g-C_3N_4) were fabricated by anodic oxidization and calcination process.First, TNTAs were prepared via the anodic oxidation of Ti foil in glycerol solution containing fluorinion and 20%deionized water. Subsequently, g-C_3N_4 film was hydrothermally grown on TNTAs via the hydrogen-bonded cyanuric acid melamine supramolecular complex. The results showed that g-C_3N_4 was successfully decorated on the TNTAs and the g-C_3N_4/TNTAs served as an efficient and stable photoanode for photoelectrochemical water splitting. The facile deposition method enables the fabrication of efficient and low-cost photoanodes for renewable energy applications. 展开更多
关键词 TiO2 nanotube arrays Graphitic carbon nitride(g-C3n4) HETEROJUnCTIOn PHOTOELECTROCHEMICAL water splitting
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纳米Al_(2)O_(3)水雾射流下陶瓷和钛合金的摩擦磨损研究
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作者 关新宇 何余康 +1 位作者 吴世雄 王成勇 《工具技术》 北大核心 2024年第9期13-18,共6页
纳米流体因润滑减摩性能优异而得到广泛应用,但纳米粒子水雾射流下摩擦副的摩擦磨损研究较少。本文开展纳米粒子水雾射流润滑下陶瓷和钛合金的摩擦磨损研究,分别制备0.10%,0.25%,0.50%,0.75%四种不同浓度的纳米Al_(2)O_(3)水溶液,进行... 纳米流体因润滑减摩性能优异而得到广泛应用,但纳米粒子水雾射流下摩擦副的摩擦磨损研究较少。本文开展纳米粒子水雾射流润滑下陶瓷和钛合金的摩擦磨损研究,分别制备0.10%,0.25%,0.50%,0.75%四种不同浓度的纳米Al_(2)O_(3)水溶液,进行两种线速度下纳米粒子水雾射流摩擦磨损对比实验,测试比较摩擦系数、磨损面积和磨痕形貌,并探讨摩擦磨损机理。实验结果表明,0.50%纳米Al_(2)O_(3)水雾射流表现出最优的减摩润滑性能。相比于干摩擦,0.50%纳米Al_(2)O_(3)水雾射流在两种不同线速度(10m/min和45m/min)下的摩擦系数分别降低了87.68%和82.81%。在纳米粒子水雾射流下,氧化锆陶瓷与钛合金的主要磨损形式为磨粒磨损,纳米Al_(2)O_(3)发挥的类轴承和保护膜作用是降低摩擦磨损的主要原因。过量的纳米粒子易发生积聚,增大磨粒磨损及微剥落。 展开更多
关键词 纳米Al_(2)O_(3) 水雾射流 陶瓷 钛合金 摩擦磨损
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Effects of Water Regime and Straw Application in Paddy Rice Season on N2O Emission from Following Wheat Growing Season 被引量:2
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作者 ZOUJian-wen HUANGYao +2 位作者 ZONGLiang-gang JIANGJing-yan ZHENGXun-hua 《Agricultural Sciences in China》 CAS CSCD 2003年第1期68-74,共7页
A split-plot experiment in a rice-winter wheat rotation system was performed to study the effects of water regime and wheat straw application in rice-growing season on N2O emission from following wheat growing season.... A split-plot experiment in a rice-winter wheat rotation system was performed to study the effects of water regime and wheat straw application in rice-growing season on N2O emission from following wheat growing season. Water regime in the rice-growing season was designed as the conventional irrigation (flooding/drainage cycle) and the permanent flooding. Wheat straw was incorporated with three rates of 0, 225 and 450 g m-2 into the paddy soil for each water regime just before rice was transplanted. N2O emission was measured by static chamber-gas chromatograph method. Results from the variance analysis indicated that the permanent flooding in rice-growing season markedly enhanced N2O emission in following wheat growing season (P=0. 003), and that the effect of straw application on N2O emission was distinguished between two water regimes. Under the conventional irrigation, incoporation of wheat straw reduced N2O emission in the following wheat growing season, while there were no significant differences in the emission for the straw application rates of 225 and 450 g m-2. No significant differences in N2O emissions were observed among the three rates of straw application for the permanent flooding regime. In addition, the seasonal variation of N2O emission was regulated by soil temperature and moisture. The daily N2O flux (Y, mg m-2 d-1) can be quantitatively described by soil temperature (T, ℃) and moisture (W, WFPS %) asY=A0+A1T+A2W+A3W2(n=23, R2 ≥0. 4159** )or y=C0+C1W+C2W2(n=23,R2≥0. 4074** ). Compared with the effect of soil temperature on N2O emission, soil moisture was an important factor regulating the seasonal pattern of N2O emission. 展开更多
关键词 WInTER-WHEAT n2O emission fluxes water regime Straw application
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Rational design of hollow oxygen deficiency-enriched NiFe_(2)O_(4)@N/rGO as bifunctional electrocatalysts for overall water splitting 被引量:3
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作者 Lei Cao Zhenhuan Li +2 位作者 Kunmei Su Maliang Zhang Bowen Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第3期595-603,共9页
Bimetallic metal organic framework(MOF)as a precursor to prepare catalysts with bifunctional catalytic activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)attracts more and more attention.Her... Bimetallic metal organic framework(MOF)as a precursor to prepare catalysts with bifunctional catalytic activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)attracts more and more attention.Herein,hollow oxygen deficiency-enriched NiFe_(2)O_(4) is synthesized by pyrolytic FeNi bimetallic MOF.The defects of rGO during carbonization can act as nucleation sites for FeNi particles.After nucleation and N doping,the FeNi particles were served as catalysts for the deposition of dissolved carbon in the defects of the N/rGO.These deposited carbon,like a bridge,connect N/rGO and hollow oxygen deficiency-enriched NiFe_(2)O_(4) together,which giving full play to the advantages of N/rGO in fast electron transfer,thereby improving its catalytic activity.The resultant NiFe_(2)O_(4)@N/rGO-800 exhibits a low overpotential of 252 mV at 20 mA cm^(-2) for OER and 157 mV at 10 mA cm^(-2) for HER in 1 M KOH,respectively.When used as bifunctional electrodes for overall water splitting,it also shows low cell voltage of 1.60 V and 1.67 V at 10 and 20 mA cm^(-2),respectively. 展开更多
关键词 Oxygen deficiency Hollow niFe_(2)O_(4) n/rGO Bifunctional electrocatalyst Overall water splitting
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K_(2)CO_(3)添加剂细水雾作用下高压氢气喷射火特性研究
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作者 祝现礼 张佳庆 +5 位作者 过羿 滕越 刘敏 章智慧 马鸿盛 王昌建 《安全与环境学报》 CAS CSCD 北大核心 2024年第11期4279-4286,共8页
为更好地抑制高压氢喷射火,研究了K_(2)CO_(3)添加剂细水雾作用下欠膨胀氢气喷射火特性。试验采用实心锥形细水雾喷嘴,考察细水雾在不同K_(2)CO_(3)添加剂质量分数、水平施加位置和施加压力下,对欠膨胀氢气喷射火火焰形态、火焰水平长... 为更好地抑制高压氢喷射火,研究了K_(2)CO_(3)添加剂细水雾作用下欠膨胀氢气喷射火特性。试验采用实心锥形细水雾喷嘴,考察细水雾在不同K_(2)CO_(3)添加剂质量分数、水平施加位置和施加压力下,对欠膨胀氢气喷射火火焰形态、火焰水平长度、羽流区温度及辐射的影响。试验采用摄像机、热电偶、辐射热流计分别测量火焰形态、空间指定点温度和辐射强度。结果表明,在含有K_(2)CO_(3)添加剂的细水雾作用下,氢气喷射火焰更明亮。细水雾压力较低(0.5 MPa)且施加位置位于火焰抬升位置时,氢气喷射火出现明显的火焰膨胀现象。通过与纯水细水雾进行对比发现,K_(2)CO_(3)添加剂细水雾对氢气喷射火稳定火焰长度、羽流区温度及热辐射的抑制效果明显,并且抑制效果随着K_(2)CO_(3)添加剂质量分数的增大而增大。 展开更多
关键词 安全工程 K_(2)CO_(3)添加剂细水雾 氢气喷射火 温度 热辐射
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石榴花水提物调节AHR/BNIP3改善糖尿病小鼠肝脏胰岛素信号 被引量:1
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作者 叶雨萌 荣雨 +2 位作者 李包娟 周克春 张䶮之 《食品工业科技》 CAS 北大核心 2024年第7期320-327,共8页
目的:探讨石榴花水提物(pomegranate flower water extract,PFW)对2型糖尿病小鼠肝脏胰岛素信号传导的影响及机制。方法:将C57BL/6J随机分为正常组、模型组、二甲双胍组(Met)、石榴花水提物低剂量组(PFWL)和石榴花水提物高剂量组(PFWH)... 目的:探讨石榴花水提物(pomegranate flower water extract,PFW)对2型糖尿病小鼠肝脏胰岛素信号传导的影响及机制。方法:将C57BL/6J随机分为正常组、模型组、二甲双胍组(Met)、石榴花水提物低剂量组(PFWL)和石榴花水提物高剂量组(PFWH)。连续给药11周后,称小鼠体质量,检测空腹血糖(FBG)、胰岛素(INS)、甘油三酯(TG)和总胆固醇(TC)的含量,计算胰岛素抵抗指数(HOMA-IR);苏木素-伊红(HE)染色观察肝组织病理变化;Western blot法检测肝组织中胰岛素受体底物1(IRS1)、p-IRS1(Ser307)、蛋白激酶B(AKT)、p-AKT(Ser473)、糖原合成酶激酶-3β(Gsk3β)、p-Gsk3β(S9)、芳香烃受体(AhR)、磷脂酰乙醇胺N-甲基转移酶(PEMT)、Bcl-2/腺病毒E1B-19kDa相互作用蛋白3(BNIP3)蛋白表达。结果:与模型组比较,PFWH组FBG、INS、HOMA-IR、TG和TC含量极显著降低(P<0.01);PFWH组小鼠肝细胞内脂肪滴明显减少;PFWH组极显著升高肝脏中IRS1、p-AKT(Ser473)/AKT、p-Gsk3β(S9)/Gsk3β、BNIP3蛋白表达(P<0.01),极显著降低p-IRS1(Ser307)/IRS1、AHR、PEMT蛋白表达(P<0.01)。结论:PFW可能通过调节AHR/BNIP3抑制肝脏脂质沉积,改善p-IRS1(Ser307)/p-AKT(Ser473)/p-GSK3β(S9)胰岛素信号通路转导。 展开更多
关键词 石榴花水取物 胰岛素信号通路 芳香烃受体 Bcl-2/腺病毒E1B-19kDa相互作用蛋白3 磷脂酰乙醇胺n-甲基转移酶
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Modulating the properties of monolayer C2N:A promising metal-free photocatalyst for water splitting
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作者 俞松 饶勇超 段香梅 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第8期390-394,共5页
Photocatalytic water splitting has gained increasing attention, since it utilizes renewable resources, such as water and solar energy, to produce hydrogen. Using the first-principles density functional theory, we inve... Photocatalytic water splitting has gained increasing attention, since it utilizes renewable resources, such as water and solar energy, to produce hydrogen. Using the first-principles density functional theory, we investigate the properties of the single layer C_2N which was successfully synthesized. We reveal that monolayer C_2N has a substantial direct band gap of 2.45 eV. To regulate its band gap, four different nonmetal elements(B, O, P, and S) on the cation and anion sites are considered. Among them, B-doped N site is the most effective one, with the lowest formation energy and a band gap of 2.01 eV. P-doped N site is the next, with a band gap of 2.08 eV, though its formation energy is higher. The band alignments with respect to the water redox levels show that, for these two dopings, the thermodynamic criterion for the overall water splitting is satisfied. We therefore predict that B-or P-doped C_2N, with an appropriate band gap and an optimal band-edge position, would be a promising photocatalyst for visible-light water splitting. 展开更多
关键词 C2n metal-free photocatalyst water splitting DOPInG first-principle calculation
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Study on variation of smoke component concentration with water mist applying
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作者 Fang Yudong 《Engineering Sciences》 EI 2014年第3期58-64,共7页
Interaction between water mist and fire smoke is studied by experiments in an ISO 9705 room, The variation of 02, CO and CO2 concentration is disclosed, and the mathematical models of smoke component con- centration w... Interaction between water mist and fire smoke is studied by experiments in an ISO 9705 room, The variation of 02, CO and CO2 concentration is disclosed, and the mathematical models of smoke component con- centration with water mist pressure and ventilation speed are established according to the experimental results. It is found in the experiment that the smoke component concentration will break when ventilation speed exceeds 1.5 kg/s. This paper provides necessary theory for water mist technology using in smoke restraining. 展开更多
关键词 water mist O2 CO CO2
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Intensive-visible-light-responsive ANbO_(2)N(A = Sr, Ba) synthesized from layered perovskite A_(5)Nb_(4)O_(15) for enhanced photoelectrochemical water splitting
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作者 Sukanya Ramaraj Jeongsuk Seo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第5期529-537,共9页
Nb-based, perovskite-type oxynitrides ANb(O,N)_(3)(A = Sr, Ba) have been significantly attractive semiconductor materials for photoelectrochemical(PEC) water splitting due to their absorption abilities of intensive-vi... Nb-based, perovskite-type oxynitrides ANb(O,N)_(3)(A = Sr, Ba) have been significantly attractive semiconductor materials for photoelectrochemical(PEC) water splitting due to their absorption abilities of intensive-visible-light. However, PEC activities of these perovskites are relatively low due to reduction of Nb species during nitridation leading to the generation of anion defects and impurity phases.Herein, we propose nitridation of A-rich, layered perovskite A_(5)Nb_(4)O_(15) as starting oxides for general synthesis of photoactive ANbO_(2)N. These layered perovskite A_(5)Nb_(4)O_(15) were completely transformed to single phase perovskite-type ANbO_(2)N by nitridation. Wavelength onsets of light absorption were observed at 700 nm for SrNbO_(2)N and at 740 nm for BaNbO_(2)N. According to X-ray photoelectron spectroscopy results,excess Lewis base A species significantly suppressed the generation of reduced species such as Nb^(4+) and Nb^(3+)during nitridation, although it led to an amorphous surface of the as-prepared oxynitride.Subsequent annealing in Ar largely enhanced surface crystallinity of ANbO_(2)N. As a result, Co(OH)_(x)/ANbO_(2)N/FTO photoanodes, prepared by loading Co(OH)_(x) electrocatalyst, showed high photocurrent density of 1.6(A = Sr) and 2.4 m A cm^(-2)(A = Ba) at 1.23 VRHEunder AM 1.5 G simulated sunlight. These results demonstrate that A-rich layered perovskite A_(5)Nb_(4)O_(15)are effective starting precursors for preparing lowdefective ANbO_(2)N, thus improving PEC water splitting activity. 展开更多
关键词 Perovskite-type oxynitride CanbO_(2)n SrnbO_(2)n BanbO_(2)n A-rich starting oxide Surface heat treatment Ar annealing Solar water oxidation
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First-principles investigation of β-Ge3N4 loaded with RuO2 cocatalyst for photocatalytic overall water splitting
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作者 Yanxia Ma Miaomiao Wang Xin Zhou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期24-32,共9页
β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic syst... β-Ge3N4 loaded with nanoparticulate RuO2 as a cocatalyst is the first successful non-oxide photocatalyst for overall water splitting.To get an insight into the working mechanism of this particular photocatalytic system,we have calculated geometrical structures of low-index surfaces forβ-Ge3N4.Analysis of surface energies indicates that the most preferentially exposed surface is(100).The band gap of surface is narrower than that of bulk due to the dangling bonds.Dissociative water adsorption on(100)surface is thermodynamically favorable.The adsorption behavior of(RuO2)n(n=2,3,and 4)clusters on theβ-Ge3N4(100)surface has been explored.It is found that all the clusters bind to(100)surface strongly by forming interfacial bonds so that the adsorptions are exothermic processes.The calculation on density of states forβ-Ge3N4(100)surface loaded with(RuO2)nclusters reveals that photo-induced electrons tend to accumulate on(RuO2)nclusters and holes tend to stay inβ-Ge3N4.Based on the theoretical indication of Type-II staggered band alignment,we have proposed that in photocatalytic water splitting reaction,oxygen evolution reaction is inclined to occur on the surface ofβ-Ge3N4 while hydrogen evolution reaction is apt to occur on(RuO2)nclusters.In a word,loading RuO2 nanoparticles as a reduction cocatalyst benefits the charge separation inβ-Ge3N4.Furthermore,attaching(RuO2)nclusters ontoβ-Ge3N4(100)surface results in the redshift of absorption edge and the increase of absorption intensity.Our calculations have reasonably explained the experimental observation on the decomposition of water into H2 and O2 after loading RuO2 cocatalyst inβ-Ge3N4 photocatalyst. 展开更多
关键词 β-Ge3n4 RUO2 COCATALYST PHOTOCATALYTIC water splitting Density functional theory
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CO_(2)和细水雾对地下变电站变压器火灾抑制作用研究
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作者 杨迎昕 焦一飞 +3 位作者 曾文慧 陈中国 米红甫 罗楠 《四川电力技术》 2024年第3期87-94,共8页
为了研究CO_(2)和细水雾对地下变电站变压器油火灾爆炸的抑制作用及其化学动力学机理,利用实验和Chemkin软件数值模拟研究了不同体积分数的细水雾和CO_(2)对化学当量比条件下20%H_(2)-CH_(4)-air混合物爆炸的影响。实验和模拟结果表明:... 为了研究CO_(2)和细水雾对地下变电站变压器油火灾爆炸的抑制作用及其化学动力学机理,利用实验和Chemkin软件数值模拟研究了不同体积分数的细水雾和CO_(2)对化学当量比条件下20%H_(2)-CH_(4)-air混合物爆炸的影响。实验和模拟结果表明:细水雾对H_(2)-CH_(4)-air混合物的火焰结构和爆炸压力的抑制作用随着细水雾体积分数的增加而愈发明显;细水雾蒸发产生的水蒸气分子和CO_(2)在反应体系中主要起稳定的第三体作用,从而减缓了爆炸链式反应的发展。另外,CO_(2)是CH_(4)氧化反应的主要产物,加入CO_(2)会削弱甲烷氧化的基元反应;反应体系中加入细水雾会通过降低基元反应温度敏感性来抑制反应体系升温,并且加入CO_(2)会促进消耗·H自由基的基元反应发生。这也是CO_(2)和细水雾共同作用抑制效果优于细水雾单独作用的原因。以上研究结果可为地下变电站变压器油火灾爆炸防治技术的发展提供理论依据。 展开更多
关键词 地下变电站 CO_(2) 细水雾 H_(2)-CH_(4)混合物 抑制作用
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