资源类型

期刊论文 196

会议视频 2

年份

2023 17

2022 19

2021 14

2020 16

2019 19

2018 6

2017 13

2016 9

2015 16

2014 8

2013 6

2012 1

2011 5

2010 5

2009 8

2008 7

2007 16

2006 3

2005 1

2004 2

展开 ︾

关键词

可持续发展 2

增材制造 2

镍基合金 2

&alpha 1

4D打印 1

9 %~12 % Cr 钢 1

&prime 1

&gamma 1

COVID-19 1

EDI 1

M23C6 碳化物 1

MOF基催化剂 1

Ni–Ti–Cu–V合金 1

Pt–Ba–Ce/γ-Al2O3 催化剂,物理化学性质,NOx存储和还原,NOx 排放,H2 还原剂 1

下穿施工 1

东亚季风 1

中微子 1

乙醇 1

二肽基肽酶4 1

展开 ︾

检索范围:

排序: 展示方式:

Thermal annealing synthesis of double-shell truncated octahedral Pt-Ni alloys for oxygen reduction reaction

Xiashuang LUO, Yangge GUO, Hongru ZHOU, Huan REN, Shuiyun SHEN, Guanghua WEI, Junliang ZHANG

《能源前沿(英文)》 2020年 第14卷 第4期   页码 767-777 doi: 10.1007/s11708-020-0667-2

摘要: Shape-controlled Pt-Ni alloys usually offer an exceptional electrocatalytic activity toward the oxygen reduction reaction (ORR) of polymer electrolyte membrane fuel cells (PEMFCs), whose tricks lie in well-designed structures and surface morphologies. In this paper, a novel synthesis of truncated octahedral PtNi alloy catalysts that consist of homogeneous Pt-Ni alloy cores enclosed by NiO-Pt double shells through thermally annealing defective heterogeneous PtNi alloys is reported. By tracking the evolution of both compositions and morphologies, the outward segregation of both PtO and NiO are first observed in Pt-Ni alloys. It is speculated that the diffusion of low-coordination atoms results in the formation of an energetically favorable truncated octahedron while the outward segregation of oxides leads to the formation of NiO-Pt double shells. It is very attractive that after gently removing the NiO outer shell, the dealloyed truncated octahedral core-shell structure demonstrates a greatly enhanced ORR activity. The as-obtained truncated octahedral Pt Ni core-shell alloy presents a 3.4-folds mass-specific activity of that for unannealed sample, and its activity preserves 45.4% after 30000 potential cycles of accelerated degradation test (ADT). The peak power density of the dealloyed truncated octahedral Pt Ni core-shell alloy catalyst based membrane electrolyte assembly (MEA) reaches 679.8 mW/cm , increased by 138.4 mW/cm relative to that based on commercial Pt/C.

关键词: dealloyed Pt-Ni alloys     truncated octahedron     double-shell     thermal annealing     oxygen reduction reaction (ORR)    

Pt-Ni nanourchins as electrocatalysts for oxygen reduction reaction

Qiaowan CHANG, Yuan XU, Shangqian ZHU, Fei XIAO, Minhua SHAO

《能源前沿(英文)》 2017年 第11卷 第3期   页码 254-259 doi: 10.1007/s11708-017-0493-3

摘要: Pt-Ni bimetallic alloys with various nanostructures have shown excellent activity toward oxygen reduction reaction (ORR). The ORR activity is highly dependent on the structure of the catalyst. In this paper, Pt-Ni nanourchins were synthesized with an average size of 50 nm consisting of 10–20 nanorods and nanooctahedra by adjusting the synthesis condition. The formation of Pt-Ni nanourchins is mainly dependent on the adding order of solvents (benzyl ether, oleylamine and oleic acid). Pt-Ni nanourchins present a reasonable high ORR activity (0.81 A/mg at 0.9 V).

关键词: Pt-Ni alloys     nanourchins     oxygen reduction reaction     shape control     fuel cells    

The cooperation effect of Ni and Pt in the hydrogenation of acetic acid

《化学科学与工程前沿(英文)》 2022年 第16卷 第3期   页码 397-407 doi: 10.1007/s11705-021-2076-4

摘要: The catalytic hydrogenation of carboxylic acid to alcohols is one of the important strategies for the conversion of biomass. Herein, a series of Ni-doped PtSn catalysts were prepared, characterized and studied in the hydrogenation of acetic acid. The Ni dopant has a strong interaction with Pt, which promotes the hydrogen adsorption, providing an activated hydrogen-rich environment for the hydrogenation. Meanwhile, the presence of Ni also improves the Pt dispersion, giving more accessible active sites for hydrogen activation. The cooperation of Pt and Ni significantly promotes the catalytic activity of the hydrogenation of acetic acid to ethanol. As a result, the catalyst with 0.1% Ni exhibits the best reaction activity, and its space time yield is twice as that of the PtSn/SiO2 catalyst. It provides a meaningful instruction on the catalyst design for the carboxylic acid hydrogenation.

关键词: acetic acid     ethanol     hydrogenation     Pt     Ni     cooperation effect    

Corrosion behavior of Fe–Cr–Ni based alloys exposed to molten MgCl2–KCl–NaCl salt with over-added

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1608-1619 doi: 10.1007/s11705-023-2349-1

摘要: MgCl2–NaCl–KCl salts mixture shows great potential as a high-temperature (> 700 °C) thermal energy storage material in next-generation concentrated solar power plants. Adding Mg into molten MgCl2–NaCl–KCl salt as a corrosion inhibitor is one of the most effective and cost-effective methods to mitigate the molten salt corrosion of commercial Fe–Cr–Ni alloys. However, it is found in this work that both stainless steel 310 and Incoloy 800H samples were severely corroded after 500 h immersion test at 700 °C when the alloy samples directly contacted with the over-added Mg in the liquid form. The corrosion attack is different from the classical impurity-driven corrosion in molten chloride salts found in previous work. Microscopic analysis indicates that Ni preferentially leaches out of alloy matrix due to the tendency to form MgNi2/Mg2Ni compounds. The Ni-depletion leads to the formation of a porous corrosion layer on both alloys, with the thickness around 204 µm (stainless steel 310) and 1300 µm (Incoloy 800H), respectively. These results suggest that direct contact of liquid Mg with Ni-containing alloys should be avoided during using Mg as a corrosion inhibitor for MgCl2–NaCl–KCl or other chlorides for high temperature heat storage and transfer.

关键词: concentrated solar power (CSP)     Mg corrosion inhibitor     Mg–Ni intermetallic     salt purification     thermal energy storage (TES)    

Ni-Ti-Cu-V四元薄膜库中微观结构和相变的组合合成和高通量表征 Article

Naila M. Al Hasan, Huilong Hou, Suchismita Sarkar, Sigurd Thienhaus, Apurva Mehta, Alfred Ludwig, Ichiro Takeuchi

《工程(英文)》 2020年 第6卷 第6期   页码 637-643 doi: 10.1016/j.eng.2020.05.003

摘要:

过去70年来,基于Ni-Ti的形状记忆合金(shape memory alloy, SMA)已得到广泛使用,但是提高 其功能稳定性仍然是实现更稳健和更高级应用的关键。本研究采用磁控溅射的方法,在热氧化的硅晶片上制备了具有成分分布的Ni-TiCu-V薄膜库。使用高通量波长色散光谱、同步加速器X射线衍射和温度相关的电阻,测量研究并 确定了成分相关的相变温度和微观结构。

关键词: Ni–Ti–Cu–V合金     组合材料科学     四元合金     形状记忆合金     薄膜库     弹性冷却     热弹性冷却     相变     高通量表征     属性映射     机器学习    

Pt–C interactions in carbon-supported Pt-based electrocatalysts

《化学科学与工程前沿(英文)》 2023年 第17卷 第11期   页码 1677-1697 doi: 10.1007/s11705-023-2300-5

摘要: Carbon-supported Pt-based materials are highly promising electrocatalysts. The carbon support plays an important role in the Pt-based catalysts by remarkably influencing the growth, particle size, morphology, dispersion, electronic structure, physiochemical property and function of Pt. This review summarizes recent progress made in the development of carbon-supported Pt-based catalysts, with special emphasis being given to how activity and stability enhancements are related to Pt–C interactions in various carbon supports, including porous carbon, heteroatom doped carbon, carbon-based binary support, and their corresponding electrocatalytic applications. Finally, the current challenges and future prospects in the development of carbon-supported Pt-based catalysts are discussed.

关键词: Pt–C interactions     Pt-based materials     carbon support     electrocatalysis    

Anodization of titanium alloys for orthopedic applications

Merve İzmir, Batur Ercan

《化学科学与工程前沿(英文)》 2019年 第13卷 第1期   页码 28-45 doi: 10.1007/s11705-018-1759-y

摘要:

In recent years, nanostructured oxide films on titanium alloy surfaces have gained significant interest due to their electrical, catalytic and biological properties. In literature, there is variety of different approaches to fabricate nanostructured oxide films. Among these methods, anodization technique, which allows fine-tuning of oxide film thickness, feature size, topography and chemistry, is one of the most popular approaches to fabricate nanostructured oxide films on titanium alloys, and it has been widely investigated for orthopedic applications. Briefly, anodization is the growth of a controlled oxide film on a metallic component attached to the anode of an electrochemical cell. This review provides an overview of the anodization technique to grow nanostructured oxide films on titanium and titanium alloys and summarizes the interactions between anodized titanium alloy surfaces with cells in terms of cellular adhesion, proliferation and differentiation. It will start with summarizing the mechanism of nanofeatured oxide fabrication on titanium alloys and then switch its focus on the latest findings for anodization of titanium alloys, including the use of fluoride free electrolytes and anodization of 3D titanium foams. The review will also highlight areas requiring further research to successfully translate anodized titanium alloys to clinics for orthopedic applications.

关键词: titanium alloys     anodization     biocompatibility     orthopedics    

Decoration of CdMoO micron polyhedron with Pt nanoparticle and their enhanced photocatalytic performance

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 1949-1961 doi: 10.1007/s11705-023-2360-6

摘要: This study aimed to prepare and apply a novel Pt/CdMoO4 composite photocatalyst for photocatalytic N2 fixation and tetracycline degradation. The Pt/CdMoO4 composite was subjected to comprehensive investigation on the morphology, structure, optical properties, and photoelectric chemical properties. The results demonstrate the dispersion of Pt nanoparticles on the CdMoO4 surface. Close contact between CdMoO4 and Pt was observed, resulting in the formation of a heterojunction structure at their contact region. Density functional theory calculation and Mott-Schottky analysis revealed that Pt possesses a higher work function value than CdMoO4, resulting in electron drift from CdMoO4 to Pt and the formation of a Schottky barrier. The presence of this barrier increases the separation efficiency of electron-hole pairs, thereby improving the performance of the Pt/CdMoO4 composite in photocatalysis. When exposed to simulated sunlight, the optimal Pt/CdMoO4 catalyst displayed a photocatalytic nitrogen fixation rate of 443.7 μmol·L‒1·g‒1·h‒1, which is 3.2 times higher than that of pure CdMoO4. In addition, the composite also exhibited excellent performance in tetracycline degradation, with hole and superoxide species identified as the primary reactive species. These findings offer practical insights into designing and synthesizing efficient photocatalysts for photocatalytic nitrogen fixation and antibiotics removal.

关键词: photocatalytic N2 fixation     Pt/CdMoO4     tetracycline degradation     Schottky barrier    

A facile synthesis of high activity cube-like Pt/carbon composites for fuel cell application

Reza B. MOGHADDAM, Samaneh SHAHGALDI, Xianguo LI

《能源前沿(英文)》 2017年 第11卷 第3期   页码 245-253 doi: 10.1007/s11708-017-0492-4

摘要: High activity catalyst with simple low-cost synthesis is essential for fuel cell commercialization. In this study, a facile procedure for the synthesis of cube-like Pt nanoparticle (Pt ) composites with high surface area carbon supports is developed by mixing precursor of Pt with carbon supports in organic batches, hence, one pot synthesis. The Pt grow with Vulcan XC-72 or Ketjen black, respectively, and then treated for 5.5 h at 185ºC (i.e., Pt /V and Pt /K). The resulting particle sizes and shapes are similar; however, Pt /K has a larger electrochemical active surface area (EASA) and a remarkably better formic acid (FA) oxidation performance. Optimization of the Pt /K composites leads to Pt /K that has been treated for 10 h at 185ºC. With a larger EASA, Pt /K is also more active in FA oxidation than the other Pt /K composites. Impedance spectroscopy analysis of the temperature treated and as-prepared (i.e., untreated) Pt /K composites indicates that Pt /K is less resistive, and has the highest limiting capacitance among the Pt /K electrodes. Consistently, the voltammetric EASA is the largest for Pt /K. Furthermore, Pt /K is compared with two commercial Pt/C catalysts, Tanaka Kikinzoku Kogyo (TKK), and Johnson Matthey (JM)Pt/C catalysts. The TKK Pt/C has a higher EASA than Pt /K, as expected from their relative particles sizes (3–4 nm vs. 6–7 nm for Pt /K), however, Pt /K has a significantly better FA oxidation activity.

关键词: synthesis     cube-like Pt     Pt/C composite     catalyst     impedance    

Highly selective catalytic hydrodeoxygenation of guaiacol to cyclohexane over Pt/TiO

Zhong HE,Xianqin WANG

《化学科学与工程前沿(英文)》 2014年 第8卷 第3期   页码 369-377 doi: 10.1007/s11705-014-1435-9

摘要: Catalysts Pt/TiO and NiMo/Al O are highly active and selective for the hydrodeoxygenation of guaiacol in a fixed bed reactor at 300 °C and 7.1 MPa, leading to the hydrogenation of aromatic ring, followed by demethylation and dehydroxylation to produce cyclohexane. For a complete hydrodeoxygenation of guaiacol, metal sites and acid sites are required. NiMo/Al O and Pt/Al O are more active and selective for cyclohexane formation as compared with Pt/TiO at 285 °C and 4 MPa. However, Pt/TiO is stable while the other two catalysts deactivate due to the nature and amount of coke formation during the reaction.

关键词: Pt/TiO2     NiMo/Al2O3     Pt/Al2O3     bio-oil     hydrodeoxygenation     guaiacol     cyclohexane    

Temperature effects of shape memory alloys (SMAs) in damage control design of steel portal frames

Xiaoqun LUO, Hanbin GE, Tsutomu USAMI

《结构与土木工程前沿(英文)》 2012年 第6卷 第4期   页码 348-357 doi: 10.1007/s11709-012-0176-4

摘要: The objective of the present study is to analytically investigate temperature effects of an axial-type seismic damper made of shape memory alloys (SMAs) equipped in steel frames. Based on a modified multilinear one dimensional constitutive model of SMAs, two types of SMAs are employed, which have different stress plateau and different stress growth rate with temperature increase. Temperature effects of SMA dampers on seismic performance upgrading are discussed in three aspects: different environment temperatures; rapid loading rate induced heat generation and different SMA fractions. The analysis indicates that the effect of environment temperature should be considered for the SMA damper in steel frames. However, the rapid loading rate induced heat generation has little adverse effect.

关键词: damage control design     shape memory alloy     temperature effect    

Concentrations of anthropogenic Pt and Pd in urban roadside soils in Xuzhou, China

WANG Xuesong, SUN Cheng

《环境科学与工程前沿(英文)》 2008年 第2卷 第4期   页码 475-479 doi: 10.1007/s11783-008-0071-3

摘要: The potential accumulation of platinum group elements (PGE) in the environment from automobile catalysts is high in urban areas, with the major sinks being roadside soils. Therefore, this investigation presented the detailed study on characterized concentrations of Pt and Pd and their enrichment ratios in urban roadside soils in Xuzhou, China in March 2003. Data from 21 roadside topsoil samples analyzed by inductively coupled plasma-mass spectrometer (ICP-MS) illustrated that the medians of concentrations of Pt and Pd were 2.9 and 2.8 ng/g, respectively. Hierarchical clustering analysis indicated that Pt and Pd were mainly from traffic emissions. Compared to unpolluted soils, computation of Pt and Pd enrichment ratios suggested that the Xuzhou roadside soils had average enrichment factors of 3.53 for Pt (in range of 1.22–5.73) and of 3.37 for Pd (in range of 1.35–4.46). Lower Pt/Pd ratios (in range of 0.35–2.86) in relation to similar studies in other countries were observed, which might be due to the different Pt/Pd ratios in Chinese automobile catalytic converters. Moreover, fine fraction (<250 ?m) contained higher concentrations of Pt and Pd compared to the coarse fraction (250–500 ?m).

关键词: platinum     detailed     different     Hierarchical     automobile catalytic    

Efficient synthesis of titania nanotubes and enhanced photoresponse of Pt decorated TiO

Yuxin YIN, Xin TAN, Feng HOU, Lin ZHAO

《化学科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 298-304 doi: 10.1007/s11705-009-0019-6

摘要: We investigated the effect of HMT (hexamethylenetetraamine) on the anodic growth of TiO nanotube arrays. The tube length increases to 4.3 μm with HMT concentration increasing to 0.04 mol·L . Adsorption of HMT on the TiO surface is shown to markedly decrease the chemical dissolution rate of tube mouth, resulting in longer nanotube length. Furthermore, Pt nanoparticles were successfully deposited on the surface of TiO nanotubes by ac electrodeposition method. The TiO /Pt composites were characterized by field emission scanning electron microscope (FESEM), X-ray photoelectron spectra (XPS), and photoelectrochemistry. An enhancement in photocurrent density has been achieved upon modification of TiO nanotubes with Pt nanoparticles.

关键词: TiO2 nanotube arrays     HMT     TiO2/Pt     Photocurrent density    

Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl

《化学科学与工程前沿(英文)》 2021年 第15卷 第6期   页码 1514-1523 doi: 10.1007/s11705-021-2092-4

摘要: A base-free catalytic system for the aerobic oxidation of 5-hydroxymethyl-2-furfural was exploited by using Pt nanoparticles immobilized onto a thermoresponsive poly(acrylamide-co-acrylonitrile)-b-poly(N-vinylimidazole) block copolymer, with an upper critical solution temperature of about 45 °C. The Pt nanocatalysts were well-dispersed and highly active for the base-free oxidation of 5-hydroxymethyl-2-furfural by molecular oxygen in water, affording high yields of 2,5-furandicarboxylic acid (up to>99.9%). The imidazole groups in the block copolymer were conducive to the improvement of catalytic performance. Moreover, the catalysts could be easily separated and recovered based on their thermosensitivity by cooling the reaction system below the upper critical solution temperature. Good stability and reusability were observed over these copolymer-immobilized catalysts with no obvious decrease in catalytic activity in the five consecutive cycles.

关键词: aerobic oxidation     base-free     5-hydroxymethyl-2-furfural     Pt nanoparticle     thermoresponsive block copolymer    

Effect of preparation parameters on catalytic properties of Pt/graphite

LIU Zhengqian, MA Jun, ZHAO Lei

《环境科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 482-487 doi: 10.1007/s11783-007-0077-2

摘要: Catalytic ozonation of aqueous solutions of oxalic acid was examined in the presence of graphite-supported platinum catalysts. The catalytic activity of graphite was significantly enhanced by loading platinum. The removal efficiency of oxalic acid was 3.0%, 47.6% and 99.3% for ozonation alone, graphite catalytic ozonation and Pt/graphite catalytic ozonation in 30 min under the experimental condition, respectively. The influence of support pretreatment, solvent, impregnation time, platinum loading amount and reduction temperature on the activity of Pt/graphite catalyst was investigated. The pretreatment of graphite support had no effect on activity improvement of Pt/graphite catalyst. Solvent and impregnation time also had no great effect on the activity. Platinum loading amount and reduction temperature influenced the catalyst activity significantly. The optimal catalytic performance of Pt/graphite was obtained when 1.0% platinum loading and 623 K of reduction temperature was adopted. The Pt/graphite catalyst was used for five times with no significant decrease in its activity and more than 90% oxalic acid removal was obtained.

标题 作者 时间 类型 操作

Thermal annealing synthesis of double-shell truncated octahedral Pt-Ni alloys for oxygen reduction reaction

Xiashuang LUO, Yangge GUO, Hongru ZHOU, Huan REN, Shuiyun SHEN, Guanghua WEI, Junliang ZHANG

期刊论文

Pt-Ni nanourchins as electrocatalysts for oxygen reduction reaction

Qiaowan CHANG, Yuan XU, Shangqian ZHU, Fei XIAO, Minhua SHAO

期刊论文

The cooperation effect of Ni and Pt in the hydrogenation of acetic acid

期刊论文

Corrosion behavior of Fe–Cr–Ni based alloys exposed to molten MgCl2–KCl–NaCl salt with over-added

期刊论文

Ni-Ti-Cu-V四元薄膜库中微观结构和相变的组合合成和高通量表征

Naila M. Al Hasan, Huilong Hou, Suchismita Sarkar, Sigurd Thienhaus, Apurva Mehta, Alfred Ludwig, Ichiro Takeuchi

期刊论文

Pt–C interactions in carbon-supported Pt-based electrocatalysts

期刊论文

Anodization of titanium alloys for orthopedic applications

Merve İzmir, Batur Ercan

期刊论文

Decoration of CdMoO micron polyhedron with Pt nanoparticle and their enhanced photocatalytic performance

期刊论文

A facile synthesis of high activity cube-like Pt/carbon composites for fuel cell application

Reza B. MOGHADDAM, Samaneh SHAHGALDI, Xianguo LI

期刊论文

Highly selective catalytic hydrodeoxygenation of guaiacol to cyclohexane over Pt/TiO

Zhong HE,Xianqin WANG

期刊论文

Temperature effects of shape memory alloys (SMAs) in damage control design of steel portal frames

Xiaoqun LUO, Hanbin GE, Tsutomu USAMI

期刊论文

Concentrations of anthropogenic Pt and Pd in urban roadside soils in Xuzhou, China

WANG Xuesong, SUN Cheng

期刊论文

Efficient synthesis of titania nanotubes and enhanced photoresponse of Pt decorated TiO

Yuxin YIN, Xin TAN, Feng HOU, Lin ZHAO

期刊论文

Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl

期刊论文

Effect of preparation parameters on catalytic properties of Pt/graphite

LIU Zhengqian, MA Jun, ZHAO Lei

期刊论文