检索结果-南通市图书馆

Performance enhancement and active sites identification of Cu-Cd bimetallic oxide derived catalysts for electrochemical CO_(2) reduction

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第4期91卷 50-58页

作者： Cai Wang Xin Hu Bairong Chen houan Ren Xiaoyu Wang Yilin Zhang Xinyu Chen Yuping Liu Qingxin Guan Wei Li State Key Laboratory of Elemento-Organic Chemistry Key Laboratory of Adv.Energy Mater.Chemistry(Ministry of Education)College of ChemistryNankai UniversityTianjin 300071China

The development of earth-abundant electrocatalysts with high performance for electrochemical CO_(2)reduction(ECR)is of great ***-based catalysts have been widely investigated for ECR due to their unique ability to generate various carbonaceous products,but directing selectivity toward one certain product and identifying the real active sites during ECR are still full of ***,after the incorporation of CdO into CuO,the Cu_(0.5)Cd_(0.5)-O catalyst achieves a 10.3-fold enhancement for CO selectivity in comparison with CuO,and a CO faradic efficiency nearly 90%with a current density around20 mA cm^(-2)could maintain at least 60 ***,a wide CO/H_(2)ratio(0.07-10)is reached on Cu_(x)Cd_(1-x)-O catalysts by varying the Cu/Cd ratio,demonstrating the potential of syngas production using such *** results of ex situ XRD,XPS,and in situ Raman reveal that the real active sites of Cu_(0.5)Cd_(0.5)-O catalysts for CO production during ECR reaction are the reconstructed mixed phases of CuCd alloy and CdCO_(3).In situ FTIR and theoretical calculations further implicate the presence of Cd related species promotes the CO desorption and inhibits the H_(2)evolution,thus leading to an enhanced CO generation.

关键词： CO_(2)reduction Cu-Cd bimetallic Real active sites CO production

在线全文

学校读者我要写书评

暂无评论

蝴蝶光束的焦散和波前特性

光学学报 2022年第16期42卷 194-200页

作者：蔡一鸣滕厚安胡俊涛兰燕平任志君钱义先浙江师范大学物理与电子信息工程学院浙江金华321004 浙江省光信息检测与显示技术研究重点实验室浙江金华321004

提出并实验产生一种基于衍射突变的新型蝴蝶光束。根据突变理论,该光束的光场结构由状态变量和控制变量共同构成的势函数所决定。由于蝴蝶突变的高维性,蝴蝶光场的焦散理论上表现为4维空间的超曲面,映射该光场到低维空间,其展现丰富多... 详细信息

提出并实验产生一种基于衍射突变的新型蝴蝶光束。根据突变理论,该光束的光场结构由状态变量和控制变量共同构成的势函数所决定。由于蝴蝶突变的高维性,蝴蝶光场的焦散理论上表现为4维空间的超曲面,映射该光场到低维空间,其展现丰富多样的光场结构。此外,通过操纵控制参数,发现蝴蝶光束能调控成不同的光场结构。研究了蝴蝶光束的频谱,发现其谱振幅能用多项式形式表示。所得数值模拟结果与实验结果吻合。该光束具有弯曲的传播轨迹和丰富的光场结构,在波前控制、光学微操纵与生物医学方面有潜在应用。

关键词：物理光学光场调控蝴蝶光束突变理论焦散

轨道角动量指向可控的紧聚焦时空波包(特邀)

在线全文

学校读者我要写书评

暂无评论

光子学报 2023年第7期52卷 36-45页

作者：莫德威曾永西陈国梁滕厚安陈建詹其文上海理工大学光电信息与计算机工程学院上海200093 上海理工大学上海市现代光学系统重点实验室上海200093 张江实验室上海201204

利用Debye积分,研究了三个相互正交的轨道角动量(包括两个正交的横向轨道角动量以及一个纵向轨道角动量)光场在紧聚焦条件下的复杂耦合现象,并演示了焦场中相位奇点在三维时空间中的演化。此外,还研究了具有不同拓扑荷数的纵向轨道角动... 详细信息

利用Debye积分,研究了三个相互正交的轨道角动量(包括两个正交的横向轨道角动量以及一个纵向轨道角动量)光场在紧聚焦条件下的复杂耦合现象,并演示了焦场中相位奇点在三维时空间中的演化。此外,还研究了具有不同拓扑荷数的纵向轨道角动量对聚焦波包整体轨道角动量指向的影响。数值结果表明,聚焦波包的整体轨道角动量指向可由纵向轨道角动量的拓扑荷数进行调控,进而实现紧聚焦时空波包的轨道角动量指向可控。这种角动量指向可控的时空波包在光学微操作、微纳加工、自旋-轨道耦合以及量子通信等领域具有潜在的应用价值。

关键词：时空光学涡旋横向轨道角动量纵向轨道角动量紧聚焦相位奇点

In-situ constructing Cu_(1)Bi_(1)bimetallic catalyst to promote the electroreduction of CO_(2)to formate by synergistic electronic and geometric effects

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2023年第4期79卷 263-271页

作者： houan Ren Xiaoyu Wang Xiaomei Zhou teng Wang Yuping Liu Cai Wang Qingxin Guan Wei Li College of Chemistry State Key Laboratory of Elemento-Organic ChemistryKey Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)Nankai UniversityTianjin 300071China

Electrochemical CO_(2)reduction to formate is a potential approach to achieving global carbon ***,Cu1Bi1bimetallic catalyst was prepared by a co-precipitation *** has a ginger like composite structure(CuO/CuBi_(2)O_(4))and exhibited a high formate faradaic efficiency of 98.07%at–0.98 V and a large current density of–56.12 ***^(-2)at–1.28 V,which is twice as high as ***,high selectivity(FE^(–)_(HCOO)>85%)is maintained over a wide potential window of 500 ***-situ Raman measurements and structure characterization revealed that the reduced Cu1Bi1bimetallic catalyst possesses abundant Cu-Bi interfaces and residual Bi-O *** abundant Cu-Bi interface structures on the catalyst surface can provide abundant active sites for CO_(2)RR,while the Bi-O structures may stabilize the CO_(2)^(*–)*** synergistic effect of abundant Cu-Bi interfaces and Bi-O species promotes the efficient synthesis of formate by following the OCHO^(*)pathway.

关键词： CO_(2)electroreduction Bimetallic catalyst Formate Cu-Bi interfaces Bi-O structure

大川中沙溪庙致密砂岩储层支撑裂缝导流能力的影响因素

在线全文

学校读者我要写书评

暂无评论

石油与天然气化工 2024年第3期53卷 92-97页

作者：张学平刘友权张鹏飞周厚安中国石油西南油气田公司天然气研究院

目的增加裂缝导流能力,提高致密砂岩气的压裂增产稳产效果。方法为了探究加砂压裂技术在大川中沙溪庙致密砂岩储层改造中的适应性,针对该储层的特点,采用API裂缝导流能力测试仪,考查了支撑剂类型及粒径、铺砂浓度、闭合压力及压裂液类... 详细信息

目的增加裂缝导流能力,提高致密砂岩气的压裂增产稳产效果。方法为了探究加砂压裂技术在大川中沙溪庙致密砂岩储层改造中的适应性,针对该储层的特点,采用API裂缝导流能力测试仪,考查了支撑剂类型及粒径、铺砂浓度、闭合压力及压裂液类型对支撑裂缝导流能力的影响。结果相同粒径陶粒的支撑裂缝导流能力大于覆膜石英砂和石英砂,但覆膜石英砂的导流能力受闭合压力的影响最小;0.106~0.212 mm石英砂与0.212~0.425 mm覆膜石英砂的不同组合支撑剂粒径(质量比分别为1∶4、1∶1和4∶1)支撑剂导流能力下降幅度相比单一支撑剂更加平缓。支撑剂组合为4∶1的裂缝导流能力高于1∶4和1∶1组合,在高闭合压力条件下接近0.212~0.425 mm覆膜石英砂用作单一支撑剂时的裂缝导流能力。在低闭合压力条件下,增加铺砂浓度促使导流能力明显增大。而随着闭合压力的增加,这种影响程度逐渐减弱。支撑剂采用(0.106~0.212 mm石英砂)∶(0.212~0.425 mm覆膜石英砂)用量为4∶1的组合支撑剂,当闭合压力为41.4 MPa时,清水压裂破胶液处理后的液测导流能力较质量分数为3%的KCl降低25.43%,返排压裂破胶液处理后的液测导流能力较质量分数为3%的KCl降低58.34%。结论实验结果指导了现场压裂支撑剂类型、粒径以及铺砂浓度等施工参数的选择,在四川盆地川中沙溪庙组致密气储层进行现场应用,获得了较好的压裂增产效果。

关键词：致密砂岩支撑剂导流能力缝宽增产效果

MoSi_2 oxidation resistance coatings for Mo_5Si_3/MoSi_2 composites

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2009年第4期28卷 418-422页

作者： YAN Jianhui XU Hongmei ZHANG houan TANG Siwen Advanced Materials Synthesis and Application Technology Laboratory Hunan University of Science and Technology Xiangtan 411201 China

In order to improve the oxidation resistance properties of 30 at.% Mo5Si3/MoSi2 composite at high temperature in air, a molybdenum disilicide coating was prepared on its surface by a molten salt technology. XRD and SEM analysis showed that only tetragonal MoSi2 phase existed in the coating after being siliconized for 5 h at 900℃. The oxidation film formed on the uncoated sample was not dense, so that oxygen diffused easily through it. The volatilization of MoO3 resulted in the oxidation film separating from the substrate. The MoSi2 coating was proved to be an effective method to prevent 30 at.% Mo5Si3/MoSi2 composites from being oxidized at 1200℃. A dense glassy SiO2 film was formed on the MoSi2 coating surface, which acted as a barrier layer for the diffusion of oxygen atoms to the substrate. The 30at.% MosSi3/MoSi2 composites with a MoSi2 coating showed much better oxidation resistance at high temperature.

关键词： oxidation resistance coatings composites molybdenum disilicide

SHRIMP dating of volcanic rock in the Zhangwu-Heishan area, West Liaoning province, China: Its relationship with coal-bearing strata

在线全文

学校读者我要写书评

暂无评论

Mining Science and Technology 2011年第5期21卷 701-708页

作者： Cai houan XU Debin Li Baofang Shao Longyi State Key Laboratory of Coal Resources and Safe Mining China University of Mining ＆ Technology Beijing 100083 China College of Energy China University of Ceosdences Beijing 100083 China College of Earth Sciences China University of Geosciences Beijing 100083 China

The Zhangwu-Heishan area is located to the east of the Fuxin-Yixian Basin and is mostly covered with volcanic rock. At various periods, different geologists had varying opinions about their age and periods of volcanic eruptions, especially on sequences between volcanic rock and main coal-bearing strata, which affect the direction of searching for coal, as well as prospecting the entire research area. During our study, we carried out detailed field investigations in this research area： observed and recorded the main representative outcrops of volcanic rock. We collected over 20 volcanic rock samples and tested the Sensitive High Resolution Ion Microprobe II （SHRIMP If） U-Pb isotope age of 11 samples. The age of our volcanic rock samples ranged between 56.0 ± 2.9 and 132.3 ± 2.3 Ma. After taking earlier investigations into consideration, we concluded that, except for a suite of paleogene olivine basalt, the volcanic rock in the Zhangwu-Heishan area is younger than the coal-bearing Shahai Formation. It is therefore most unlikely to find coal seams equivalent to those of the early Cretaceous Shahai Formation in Fuxin Basin below vol- canic rock.

关键词： West Liaoning provinceZhangwu-Heishan areaVolcanic rockSHRIMP U-Pb isotopic ageCoal-bearing strata

轧制变形及再结晶00Cr12铁素体不锈钢中的{011}/{011}近奇异晶界

在线全文

学校读者我要写书评

暂无评论

中国科学：技术科学 2024年第3期54卷 459-476页

作者：黄新宇王卫国 ROHRER Gregory S 徐刚陈松冯小铮张厚安陈文哲周邦新福建理工大学晶界工程研究所福州350118 福建理工大学材料科学与工程学院福州350118 Department of Materials Science and Engineering Carnegie Mellon UniversityPittsburgh 15213-3890USA 厦门理工学院材料科学与工程学院厦门361024 上海大学材料研究所上海200072

不同于低层错能面心立方结构的奥氏体不锈钢,高层错能体心立方结构的铁素体不锈钢在形变及再结晶等组织重构过程中很难形成结构稳定且十分耐蚀的奇异晶界(共格孪晶界).研究{011}/{011}近奇异晶界的影响因素和形成机理,将有可能为改善铁... 详细信息

不同于低层错能面心立方结构的奥氏体不锈钢,高层错能体心立方结构的铁素体不锈钢在形变及再结晶等组织重构过程中很难形成结构稳定且十分耐蚀的奇异晶界(共格孪晶界).研究{011}/{011}近奇异晶界的影响因素和形成机理,将有可能为改善铁素体不锈钢,特别是低Cr铁素体不锈钢晶间腐蚀性能提供晶界工程新思路.本文选用经固溶处理和组织均匀化处理的00Cr12低Cr铁素体不锈钢为实验材料,5个平行试样分别在350℃,500℃,580℃,650℃和690℃进行厚度减缩量为70%的单向轧制变形后,立即进行750℃、2 h再结晶退火处理.使用基于电子背散射衍射和五参数分析的晶界界面匹配表征方法对上述样品进行测试和分析发现,轧制温度对00Cr12铁素体不锈钢再结晶{011}/{011}近奇异晶界比例有显著影响,再结晶后的{011}/{011}近奇异晶界比例随再结晶退火前轧制温度的升高先上升再下降,其中经650℃轧制的样品,其再结晶后{011}/{011}近奇异晶界比例达到极大值6.82%.取向分布函数(ODF)和重叠极图晶界迹线分析表明,经650℃轧制的样品,其再结晶组织中形成了强的{011}织构;具有{011}及其漫散取向的晶粒之间较多地存在/θ取向差关系(θ为绕的旋转角),其关联晶界为{011}/{011}近奇异晶界,这是经650℃轧制的样品,其再结晶后{011}/{011}近奇异晶界比例达到极大值的原因.离线原位表面侵蚀实验表明,{011}/{011}近奇异晶界的腐蚀抗力显著高于一般晶界.因此,基于本文研究结果,进一步调控并提高{011}/{011}近奇异晶界的比例将有助于从根本上显著改善00Cr12铁素体不锈钢晶间腐蚀性能.

关键词： 00Cr12铁素体不锈钢近奇异晶界晶界界面匹配晶间腐蚀

冻融循环作用下约束浆锚搭接连接性能试验研究

在线全文

学校读者我要写书评

暂无评论

水利与建筑工程学报 2024年第5期22卷 98-105页

作者：孙杰孙和廖海峰王厚安武汉科技大学城市建设学院湖北武汉430065 中国市政工程中南设计研究总院有限公司湖北武汉430010

为了研究冻融环境下约束浆锚搭接试件的连接性能,以灌浆料种类(高强水泥基灌浆料、环氧树脂灌浆料、地聚物灌浆料)和冻融循环次数(0次、50次、100次)为主要试验参数,进行27个约束浆锚搭接试件的单向拉拔试验,分析试件的外观变化,破坏形... 详细信息

为了研究冻融环境下约束浆锚搭接试件的连接性能,以灌浆料种类(高强水泥基灌浆料、环氧树脂灌浆料、地聚物灌浆料)和冻融循环次数(0次、50次、100次)为主要试验参数,进行27个约束浆锚搭接试件的单向拉拔试验,分析试件的外观变化,破坏形态、极限荷载、荷载-位移曲线及荷载-应变曲线。结果表明:常温下和冻融50次后,试件均发生钢筋拉断破坏;100次后试件发生劈裂破坏。常温下和冻融50次后三种灌浆料的约束浆锚搭接试件的连接性能均可靠;冻融循环次数达到100次,极限荷载大幅降低。试件的极限粘结强度随着冻融循环次数的增加逐渐降低。约束浆锚搭接连接性能可靠,三种灌浆料均能满足锚固要求。

关键词：约束浆锚搭接冻融循环单向拉伸锚固能力极限粘结强度