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期刊论文 9

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S-N曲线 1

上举力 1

冲刷评估 1

分数阶离散系统；神经网络；DNA加密；彩色图像加密 1

大坝安全 1

岩体冲刷 1

岩块稳定性 1

掺气 1

树脂灌注式螺栓 1

疲劳 1

结构加强 1

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Catalytic combustion of methane over a highly active and stable NiO/CeO

Xiuhui Huang, Junfeng Li, Jun Wang, Zeqiu Li, Jiayin Xu

《化学科学与工程前沿（英文）》 2020年 第14卷 第4期   页码 534-545 doi: 10.1007/s11705-019-1821-4

摘要： In the last decades, many reports dealing with technology for the catalytic combustion of methane (CH ) have been published. Recently, attention has increasingly focused on the synthesis and catalytic activity of nickel oxides. In this paper, a NiO/CeO catalyst with high catalytic performance in methane combustion was synthesized via a facile impregnation method, and its catalytic activity, stability, and water-resistance during CH combustion were investigated. X-ray diffraction, low-temperature N adsorption, thermogravimetric analysis, Fourier transform infrared spectroscopy, hydrogen temperature programmed reduction, methane temperature programmed surface reaction, Raman spectroscopy, electron paramagnetic resonance, and transmission electron microscope characterization of the catalyst were conducted to determine the origin of its high catalytic activity and stability in detail. The incorporation of NiO was found to enhance the concentration of oxygen vacancies, as well as the activity and amount of surface oxygen. As a result, the mobility of bulk oxygen in CeO was increased. The presence of CeO prevented the aggregation of NiO, enhanced reduction by NiO, and provided more oxygen species for the combustion of CH . The results of a kinetics study indicated that the reaction order was about 1.07 for CH and about 0.10 for O over the NiO/CeO catalyst.

关键词： methane combustion     NiO/CeO2 catalyst     interaction     oxygen vacancy     kinetic study    

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Methane partial oxidation over NiO-MgO/Ce

Piyawat PUE-ON, Vissanu MEEYOO, Thirasak RIRKSOMBOOON

《化学科学与工程前沿（英文）》 2013年 第7卷 第3期   页码 289-296 doi: 10.1007/s11705-013-1345-2

摘要： Methane partial oxidation (MPO) is considered as an alternative method to produce hydrogen because it is an exothermic reaction to afford a suitable H /CO ratio of 2. However, carbon deposition on a catalyst is observed as a major cause of catalyst deactivation in MPO. In order to find suitable catalysts that prevent the carbon deposition, NiO-MgO/Ce Zr O (CZO) supported catalysts were prepared via the co-impregnation (C) and sequential incipient wetness impregnation (S) methods. The amount of Ni loading was fixed at 15 wt-% whereas the amount of MgO loading was varied from 5 to 15 wt-%. The results revealed that the addition of MgO shifted the light-off temperatures to higher temperatures. This is because the Ni surface was partially covered with MgO, and the strong interaction between NiO and NiMgO over CZO support led to the difficulty in reducing NiO to active Ni and thus less catalytic activity. However, among the catalysts tested, the 15Ni5Mg/CZO (S) catalyst exhibited the best catalytic stability for MPO after 18 h on stream at 750°C. Moreover, this catalyst had a better resistance to carbon deposition due to its high metallic Ni dispersion at high temperature.

关键词： methane partial oxidation     NiO     ceria-zirconia     MgO     mixed oxide solid solution    

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Mechanical properties characterization of different types of masonry infill walls

André FURTADO, Hugo RODRIGUES, António ARÊDE, Humberto VARUM

《结构与土木工程前沿（英文）》 2020年 第14卷 第2期   页码 411-434 doi: 10.1007/s11709-019-0602-y

摘要： It is remarkable, the recent advances concerning the development of numerical modeling frameworks to simulate the infill panels’ seismic behavior. However, there is a lack of experimental data of their mechanical properties, which are of full importance to calibrate the numerical models. The primary objective of this paper is to present an extensive experimental campaign of mechanical characterization tests of infill masonry walls made with three different types of masonry units: lightweight vertical hollow concrete blocks and hollow clay bricks. Four different types of experimental tests were carried out, namely: compression strength tests, diagonal tensile strength tests, and flexural strength tests parallel and perpendicular to the horizontal bed joints. A total amount of 80 tests were carried out and are reported in the present paper. The second objective of this study was to compare the mechanical properties of as-built and existing infill walls. The results presented and discussed herein, will be in terms of strain-stress curves and damages observed within the tests. It was observed a fragile behavior in the panels made with hollow clay horizontal bricks, without propagation of cracks. The plaster increased the flexural strength by 57%.

关键词： masonry infill walls     experimental characterization     compression strength     shear diagonal strength     flexural strength    

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基于纳米金/介孔NiO/泡沫镍纳米复合材料的微型电极用于地下水重金属检测 Article

薛博元, 杨倩, 夏楷东, 李志宏, 陈宇徽, 张大奕, 周小红

《工程（英文）》 2023年 第27卷 第8期   页码 199-208 doi: 10.1016/j.eng.2022.06.005

摘要：

Heavy metals, notably Pb2+ and Cu2+, are some of the most persistent contaminants found in groundwater. Frequent monitoring of these metals, which relies on efficient, sensitive, cost-effective, and reliable methods, is a necessity. We present a nanocomposite-based miniaturized electrode for the concurrent measurement of Pb2+ and Cu2+ by exploiting the electroanalytical technique of square wave voltammetry. We also propose a facile in situ hydrothermal calcination method to directly grow binder-free mesoporous NiO on a three-dimensional nickel foam, which is then electrochemically seeded with gold nanoparticles (AuNPs). The meticulous design of a low-barrier Ohmic contact between mesoporous NiO and AuNPs facilitates target-mediated nanochannel-confined electron transfer within mesoporous NiO. As a result, the heavy metals Pb2+ (0.020 mg·L−1 detection limit, 2.0–16.0 mg·L−1 detection range) and Cu2+ (0.013 mg·L−1 detection limit, 0.4–12.8 mg·L−1 detection range) can be detected simultaneously with high precision. Furthermore, other heavy metal ions and common interfering ions found in groundwater showed negligible impacts on the electrode's performance, and the recovery rate of groundwater samples varied between 96.3% ± 2.1% and 109.4% ± 0.6%. The compactness, flexible shape, low power consumption, and ability to remotely operate our electrode pave the way for onsite detection of heavy metals in groundwater, thereby demonstrating the potential to revolutionize the field of environmental monitoring.

关键词： AuNPs     Mesoporous NiO     Miniaturized electrode     Heavy metal ions     Groundwater     Square wave voltammetry    

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Characterization and catalytic activity of soft-templated NiO-CeO

Luciano Atzori, Maria Giorgia Cutrufello, Daniela Meloni, Barbara Onida, Delia Gazzoli, Andrea Ardu, Roberto Monaci, Maria Franca Sini, Elisabetta Rombi

《化学科学与工程前沿（英文）》 2021年 第15卷 第2期   页码 251-268 doi: 10.1007/s11705-020-1951-8

摘要： Nanosized NiO, CeO and NiO-CeO mixed oxides with different Ni/Ce molar ratios were prepared by the soft template method. All the samples were characterized by different techniques as to their chemical composition, structure, morphology and texture. On the catalysts submitted to the same reduction pretreatment adopted for the activity tests the surface basic properties and specific metal surface area were also determined. NiO and CeO nanocrystals of about 4 nm in size were obtained, regardless of the Ni/Ce molar ratio. The Raman and X-ray photoelectron spectroscopy results proved the formation of defective sites at the NiO-CeO interface, where Ni species are in strong interaction with the support. The microcalorimetric and Fourier transform infrared analyses of the reduced samples highlighted that, unlike metallic nickel, CeO is able to effectively adsorb CO , forming carbonates and hydrogen carbonates. After reduction in H at 400 °C for 1 h, the catalytic performance was studied in the CO and CO co-methanation reaction. Catalytic tests were performed at atmospheric pressure and 300 °C, using CO/CO /H molar compositions of 1/1/7 or 1/1/5, and space velocities equal to 72000 or 450000 cm ∙h ∙g . Whereas CO was almost completely hydrogenated in any investigated experimental conditions, CO conversion was strongly affected by both the CO/CO /H ratio and the space velocity. The faster and definitely preferred CO hydrogenation was explained in the light of the different mechanisms of CO and CO methanation. On a selected sample, the influence of the reaction temperature and of a higher number of space velocity values, as well as the stability, were also studied. Provided that the Ni content is optimized, the NiCe system investigated was very promising, being highly active for the CO co-methanation reaction in a wide range of operating conditions and stable (up to 50 h) also when submitted to thermal stress.

关键词： soft template method     NiO-CeO2 catalysts     CO and CO2 co-methanation     synthetic natural gas production    

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考虑射流掺气的改进冲刷模型

Rafael Duarte,António Pinheiro,Anton J. Schleiss

《工程（英文）》 2016年 第2卷 第3期   页码 294-301 doi: 10.1016/J.ENG.2016.03.003

摘要：

基于受高速射流冲击的水垫塘中掺气对岩块稳定性影响的系统试验研究，本文给出了一种基于物理特性冲刷模型的适应性研究成果。在综合冲刷模型中实现了对射流掺气模型的改进，使其得以再现有关冲刷形成的物理– 机械过程，其中涉及三相，即水、岩体和空气。改进方法考虑了因挟带气泡引起的掺气射流动量减少以及射流扩散剪切层的能量消耗。岩块从岩体脱离取决于掺气的时均压强系数及修正的最大动力冲击系数的组合，对于深水垫塘中的高速射流，该系数为定值0.2。上述改进模型的模拟结果与卡里巴大坝冲坑原型观测结果吻合良好。

关键词： 掺气     上举力     岩体冲刷     大坝安全     高速射流     岩块稳定性     冲刷评估    

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A multi-integrated approach on toxicity effects of engineered TiO

DINIZ,Joana LOURENÇO,Isabel PERES,Luisa CASTRO,José Brito CORREIA,Joana PEREIRA,Isabel FERREIRA,António

《环境科学与工程前沿（英文）》 2015年 第9卷 第5期   页码 793-803 doi: 10.1007/s11783-015-0775-0

摘要： The new properties of engineered nanoparticles drive the need for new knowledge on the safety, fate, behavior and biologic effects of these particles on organisms and ecosystems. Titanium dioxide nanoparticles have been used extensively for a wide range of applications, e.g, self-cleaning surface coatings, solar cells, water treatment agents, topical sunscreens. Within this scenario increased environmental exposure can be expected but data on the ecotoxicological evaluation of nanoparticles are still scarce. The main purpose of this work was the evaluation of effects of TiO nanoparticles in several organisms, covering different trophic levels, using a battery of aquatic assays. Using fish as a vertebrate model organism tissue histological and ultrastructural observations and the stress enzyme activity were also studied. TiO nanoparticles (Aeroxide® P25), two phase composition of anatase (65%) and rutile (35%) with an average particle size value of 27.6±11 nm were used. Results on the EC for the tested aquatic organisms showed toxicity for the bacteria, the algae and the crustacean, being the algae the most sensitive tested organism. The aquatic plant showed no effect on growth. The fish showed no effect on a 21 day survival test, though at a biochemical level the cytosolic Glutathione-S-Transferase total activity, in intestines, showed a general significant decrease ( <0.05) after 14 days of exposure for all tested concentrations. The presence of TiO nanoparticles aggregates were observed in the intestine lumen but their internalization by intestine cells could not be confirmed.

关键词： ecotoxicity     enzymatic analysis     histology     transmission electron microscopy (TEM)     TiO2-nanoparticles    

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一种基于离散分数阶混沌系统和DNA序列运算的新型彩色图像加密算法 Research Articles

陈立平1,尹昊1,袁利国2,António M. LOPES3,J. A. Tenreiro MACHADO4,吴然超5

《信息与电子工程前沿（英文）》 2020年 第21卷 第6期   页码 809-962 doi: 10.1631/FITEE.1900709

摘要： 提出一种基于动态DNA编码和混沌的新型彩色图像加密算法。将一个三神经元分数阶离散Hopfield神经网络作为伪随机混沌序列发生器。其初值由外部输入的五位密钥以及明文图像的哈希值计算得来。外部密钥包含分数阶离散Hopfield神经网络的离散步长和阶次。哈希值由SHA-2函数计算得到。在保证较大密钥空间的同时，提高了算法对明文图像的敏感性。在此基础上，提出一种新型三维投影置乱方法，置乱图像红、绿、蓝信号通道中像素位置。DNA编码以及扩散被用于扩散图像信息。使用离散分数阶Hopfield神经网络生成的伪随机数序列确定每个像素的编码规则，用以保证编码方式的多样性。最后，运用置乱II和XOR提升算法的安全性。实验结果和安全性分析表明，该算法具有较好安全性，能够抵御多种典型攻击。

关键词： 分数阶离散系统；神经网络；DNA加密；彩色图像加密    

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基于统计分析的树脂灌注式螺栓连接疲劳强度评价

José António Fonseca de Oliveira Correia, Bruno Alexandre Silva Pedrosa, Patrícia

《工程（英文）》 2017年 第3卷 第6期   页码 795-805 doi: 10.1016/j.eng.2017.12.001

摘要：
在对老旧的螺栓和铆接金属桥进行修补和加固时可以使用不同的方案。由于铆接链接技术目前并不常用，连接它需要特定的设备和熟练的工人。另一种解决方案是使用焊接。但是，老旧钢材的可焊性较差。螺栓是一种非常可行的替代解决方案，并且常用于修复旧金属桥。装配螺栓的解决方案成本高昂，另一种方法是使用树脂灌注式螺栓。带有预紧力的树脂灌注式老旧螺栓连接的受力性能已经用准静态和蠕变试验进行了研究，然而，关于这些连接节点的滑移和疲劳行为的文献很少。本文概述了几位研究者的实验项目，旨在评估单侧受剪和双侧受剪的树脂灌注式螺栓连接的疲劳行为。对有预紧力的标准螺栓和有预紧力的树脂灌注式螺栓的连接节点的实验数据进行比较分析，显示后者的疲劳强度较低。但欧洲规范3（EC3）对树脂灌注式螺栓和标准螺栓的连接节点提出的疲劳强度曲线大致相同，这应得到足够的重视。此外，本研究还展示了使用黏结螺栓连接的可行性研究。最后的研究是用高强度低合金结构钢板和用于金属黏结的丙烯酸结构黏结剂进行的。针对两个实际工程案例，使用线性化边界及Castillo 和Fernández-Canteli 模型对疲劳实验数据进行统计分析。最终提出疲劳设计曲线，并与欧洲和北美规范中的几个设计建议进行比较。

关键词： 疲劳     连接     结构加强     S-N曲线     树脂灌注式螺栓    

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标题 作者 时间 类型 操作

Catalytic combustion of methane over a highly active and stable NiO/CeO

Xiuhui Huang, Junfeng Li, Jun Wang, Zeqiu Li, Jiayin Xu

期刊论文

Methane partial oxidation over NiO-MgO/Ce

Piyawat PUE-ON, Vissanu MEEYOO, Thirasak RIRKSOMBOOON

期刊论文

Mechanical properties characterization of different types of masonry infill walls

André FURTADO, Hugo RODRIGUES, António ARÊDE, Humberto VARUM

期刊论文

基于纳米金/介孔NiO/泡沫镍纳米复合材料的微型电极用于地下水重金属检测

薛博元, 杨倩, 夏楷东, 李志宏, 陈宇徽, 张大奕, 周小红

期刊论文

Characterization and catalytic activity of soft-templated NiO-CeO

Luciano Atzori, Maria Giorgia Cutrufello, Daniela Meloni, Barbara Onida, Delia Gazzoli, Andrea Ardu, Roberto Monaci, Maria Franca Sini, Elisabetta Rombi

期刊论文

考虑射流掺气的改进冲刷模型

Rafael Duarte,António Pinheiro,Anton J. Schleiss

期刊论文

A multi-integrated approach on toxicity effects of engineered TiO

DINIZ,Joana LOURENÇO,Isabel PERES,Luisa CASTRO,José Brito CORREIA,Joana PEREIRA,Isabel FERREIRA,António

期刊论文

一种基于离散分数阶混沌系统和DNA序列运算的新型彩色图像加密算法

陈立平1,尹昊1,袁利国2,António M. LOPES3,J. A. Tenreiro MACHADO4,吴然超5

期刊论文

基于统计分析的树脂灌注式螺栓连接疲劳强度评价

José António Fonseca de Oliveira Correia, Bruno Alexandre Silva Pedrosa, Patrícia

期刊论文