资源类型

期刊论文 155

会议视频 1

年份

2023 10

2022 12

2021 19

2020 10

2019 13

2018 5

2017 8

2016 8

2015 3

2014 7

2013 4

2012 7

2011 7

2010 10

2009 4

2008 6

2007 3

2006 4

2005 4

2004 2

展开 ︾

关键词

三塔悬索桥 2

3D打印 1

Cuk矩阵变换器 1

MIMO雷达；波形设计；谱分解；分式二次约束二次规划 1

Mie散射 1

N∶P比值 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

S型钢丝研制 1

乙烷干重整 1

事件定位 1

二氧化碳 1

二维正交方阵码（2D-OOSC） 1

互感器 1

五模材料 1

仿真 1

传动比 1

传热强化 1

位移特征 1

信号叠加 1

展开 ︾

检索范围：

排序： 展示方式：

Preparation of ceria-zirconia solid solution with enhanced oxygen storage capacity and redox performance

Lijing MENG, Licheng LIU, Xuehong ZI, Hongxing DAI, Hong HE, Zhen ZHAO, Xinping WANG,

《环境科学与工程前沿（英文）》 2010年 第4卷 第2期   页码 164-171 doi: 10.1007/s11783-010-0019-2

摘要： A new method called ultrasonic-assisted membrane reaction (UAMR) was reported for the fabrication of ceria-zirconia solid solution. A series of ceria-zirconia solid solutions with different Ce/Zr molar ratios were prepared by the UAMR method and characterized by X-ray diffraction (XRD), N adsorption, hydrogen temperature-programmed reduction (H-TPR), scanning electron microscope (SEM), and transmission electron microscopy (TEM) techniques. The UAMR method proved to be superior, especially when the Ce/Zr molar ratio was lower than 1, in fabricating ceria-zirconia solid solutions with large BET surface area, high oxygen storage capacity (OSC), and low reduction temperature.

关键词： membrane reaction     ceria-zirconia     Ce/Zr molar ratio     solid solution     hydrogen temperature-programmed reduction (H2-TPR)    

HTML PDF 收藏

An investigation of the CHOH and CO selectivity of CO hydrogenation over Cu–Ce–Zr catalysts

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 950-962 doi: 10.1007/s11705-022-2162-2

摘要： A series of Cu–Ce–Zr catalysts with different Ce contents are applied to the hydrogenation of CO2 to CO/CH3OH products. The Cu–Ce–Zr catalyst with 2 wt% Ce loading shows higher CO selectivity (SCO = 0.0%–87.8%) from 200–300 °C, while the Cu–Ce–Zr catalyst with 8 wt% Ce loading presents higher CO2 conversion ( XCO2 = 5.4%–15.6%) and CH3OH selectivity ( SCH3OH = 97.8%–40.6%). The number of hydroxyl groups and solid solution nature play a significant role in changing the reaction pathway. The solid solution enhances the CO2 adsorption ability. At the CO2 adsorption step, a larger number of hydroxyl groups over the Cu–Ce–Zr catalyst with 8 wt% Ce loading leads to the production of H-containing adsorption species. At the CO2 hydrogenation step, a larger number of hydroxyl groups assists in encouraging the further hydrogenation of intermediate species to CH3OH and improving the hydrogenation rate. Hence, the Cu–Ce–Zr catalyst with 8 wt% Ce loading favors CH3OH selectivity and CO2 activation, while CO is preferred on the Cu–Ce–Zr catalyst with 2 wt% Ce loading, a smaller number of hydroxyl groups and a solid solution nature. Additionally, high-pressure in situ diffuse reflectance infrared Fourier transform spectroscopy shows that CO is produced from formate decomposition and that both monodentate formate and bidentate formate are active intermediate species of CO2 hydrogenation to CH3OH.

关键词： CO2 hydrogenation     Cu–Ce–Zr     hydroxyls     CO/CH3OH selectivity    

HTML PDF 收藏

PM-support interfacial effect and oxygen mobility in Pt, Pd or Rh-loaded (Ce,Zr,La)O catalysts

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1369-z

摘要：

• Pt/CZL exhibits the optimum catalytic performance for HC and NOx elimination.

关键词： Precious metal-loaded (Ce     Zr     La)O2 catalysts     Oxygen mobility     Catalytic performance    

HTML PDF 收藏

Tailoring the simultaneous abatement of methanol and NO on Sb-Ce-Zr catalysts via copper modification

《环境科学与工程前沿（英文）》 2022年 第16卷 第10期 doi: 10.1007/s11684-022-1565-0

摘要：

● Cu addition enhances CH3OH oxidation and alleviates its inhibitory effect on SCR.

关键词： Copper modification     Sb-CeZr2Ox catalyst     NOx     Methanol     Simultaneous removal    

HTML PDF 收藏

The influence of the NCO/OH ratio and the 1,6-hexanediol/dimethylol propionic acid molar ratio on the

Jiao Feng, Qiuhao Lu, Weimin Tan, Kequan Chen, Pingkai Ouyang

《化学科学与工程前沿（英文）》 2019年 第13卷 第1期   页码 80-89 doi: 10.1007/s11705-018-1763-2

摘要：

1,5-Pentamethylene diisocyanate, a novel aliphatic diisocyanate formed from bio-based 1,5-pentamethylenediamine, has been used as a hard segmented material to synthesize polyurethane. In this study, several waterborne polyurethane (WPU) dispersions have been successfully prepared by a prepolymer process from 1,5-pentamethylene diisocyanate poly(polyether) with different NCO/OH ratios and 1,6-hexanediol (HDO)/dimethylol propionic acid (DMPA) molar ratios. The Fourier transform infrared (FTIR) spectra, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, and a mechanical tensile test were used to investigate the structures, thermal stability, phase separation, crystallinity, mechanical properties, and adhesive performance of the WPU dispersions. The FTIR results indicate that the degree of hydrogen bonding and the numbers of urea groups increase as the NCO/OH ratio and HDO/DMPA molar ratio increase. Furthermore, the phase separation increases and the thermal stability decreases as the NCO/OH ratio increases or the HDO/DMPA molar ratio decreases. Finally, WPU3.0-2.4 (NCO/OH=3, HDO/DMPA=2.4) exhibits a maximum tensile strength and shear strength, pointing to its possible use as an adhesive. These results could provide a very valuable reference for industrial applications of WPU.

关键词： 1     5-pentamethylene diisocyanate     polyurethane     water based    

HTML PDF 收藏

Promotion of transition metal oxides on the NH

Weiman Li, Haidi Liu, Yunfa Chen

《环境科学与工程前沿（英文）》 2017年 第11卷 第2期 doi: 10.1007/s11783-017-0914-x

摘要： Manganese and chromium oxides promote the NH -SCR activity of Zr-Ce mixed oxide. Cr-Zr-Ce mixed oxide exhibited>80% NO conversion at a wide temperature window. More acid sites and higher reducibility may responsible for the high SCR ability. Chromium oxide and manganese oxide promoted ZrO -CeO catalysts were prepared by a homogeneous precipitation method for the selective catalytic reduction of NO with NH . A series of characterization including X-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), Brunauer–Emmett–Teller (BET) surface area analysis, H temperature-programmed reduction (H -TPR), and X-ray photoelectron spectroscopy (XPS) were used to evaluate the influence of the physicochemical properties on NH -SCR activity. Cr-Zr-Ce and Mn-Zr-Ce catalysts are much more active than ZrO -CeO binary oxide for the low temperature NH -SCR, mainly because of the high specific surface area, more surface oxygen species, improved reducibility derived from synergistic effect among different elements. Mn-Zr-Ce catalyst exhibited high tolerance to SO and H O. Cr-Zr-Ce mixed oxide exhibited>80% NO conversion at a wide temperature window of 100°C–300°C. DRIFT studies showed that the addition of Cr is beneficial to the formation of Bronsted acid sites and prevents the formation of stable nitrate species because of the presence of Cr . The present mixed oxide can be a candidate for the low temperature abatement of NO .

关键词： NH3-selective catalytic reduction     NOx     Low temperature     Cr-Zr-Ce    

HTML PDF 收藏

Cooperative effect between copper species and oxygen vacancy in CeZrCuO catalysts for carbon monoxide oxidation

《化学科学与工程前沿（英文）》 2021年 第15卷 第6期   页码 1524-1536 doi: 10.1007/s11705-021-2106-2

摘要： The effects of Zr doping on the existence of Cu and the catalytic performance of Ce0.7−xZrxCu0.3O2 for CO oxidation were investigated. The characterization results showed that all samples have a cubic structure, and a small amount of Zr doping facilitates Cu2+ ions entering the CeO2 lattice, but excessive Zr doping leads to the formation of surface CuO crystals again. Thus, the number of oxygen vacancies caused by the Cu2+ entering the lattice (e.g., Cu2+–□–Ce4+; □: oxygen vacancy), and the amount of reducible copper species caused by CuO crystals, varies with the Zr doping. Catalytic CO oxidation tests indicated that the oxygen vacancy and the reducible copper species were the adsorption and activation sites of O2 and CO, respectively, and the cooperative effects between them accounted for the high CO oxidation activity. Thus, the samples x = 0.1 and 0.3, which possessed the most oxygen vacancy or reducible copper species, showed the best activity for CO oxidation, with full CO conversion obtained at 110 °C. The catalyst is also stable and has good resistance to water during the reaction.

关键词： Ce–Zr–Cu–O     CO oxidation     reducible copper species     oxygen vacancy     cooperative effect    

HTML PDF 收藏

Promoting effect of Zr on the catalytic combustion of methane over Pd/γ-Al

Hongbo NA,Tianle ZHU,Zhiming LIU,Yifei SUN

《环境科学与工程前沿（英文）》 2014年 第8卷 第5期   页码 659-665 doi: 10.1007/s11783-013-0613-1

摘要： The effect of Zr on the catalytic performance of Pd/γ-Al O for the methane combustion was investigated. The results show that the addition of Zr can improve the activity and stability of Pd/γ-Al O catalyst, which, based on the catalyst characterization (N adsorption, XRD, CO-Chemisorption, XPS, CH -TPR and O -TPO), is ascribed to the interaction between Pd and Zr. The active phase of methane combustion over supported palladium catalyst is the Pd /Pd mixture. Zr addition inhibits Pd aggregation and enhances the redox properties of active phase Pd / Pd . H reduction could effectively reduce the oxidation degree of Pd species and regenerate the active sites (Pd / Pd ).

关键词： Pd-Zr/Al2O3     methane     catalytic combustion     catalyst regeneration    

HTML PDF 收藏

Modeling of Ce(IV) transport through a dispersion flat combined liquid membrane with carrier P507

Liang PEI,Liming WANG,Zhanying MA

《环境科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 503-509 doi: 10.1007/s11783-013-0540-1

摘要： A mathematical model for the transport of Ce(IV) from hydrochloric acid solutions through dispersion flat combined liquid membrane (DFCLM) with contain 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester (P507) as the carrier, dissolved in kerosene as the membrane solution have been studied. This process of facilitated transport, based on membrane technology, is a variation on the conventional technique of solvent extraction and may be described mathematically using Fick’s second law. The equations for transport velocity are derived considering the diffusion of P507 and its metallic complexes through the liquid membrane. In this work, the system is considered to be in a transient state, and chemical reaction between Ce(IV) and the carrier to take place only at the solvent–aqueous interfaces. Model concentration profiles are obtained for the Ce(IV), from which extraction velocities are predicted. The experimental and simulated Ce(IV) extractions showed similar tendencies for a high Ce(IV) concentration and acidity case.The model results indicate that high initial Ce(IV) concentrations and acidity both have detrimental effects on Ce(IV) extraction and stripping. The diffusion coefficient of Ce(IV) in the membrane and the thickness of diffusion layer between feed phase and membrane phase are obtained and the values are 6.31 × 10 m ·s and 31.2 μm, respectively. The results are in good agreement with experimental results.

关键词： Dispersion flat combined liquid membrane (DFCLM)     dispersion phase     feed phase     2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester     Ce (IV)    

HTML PDF 收藏

Research progress of defect-engineered UiO-66(Zr) MOFs for photocatalytic hydrogen production

《能源前沿（英文）》 2021年 第15卷 第3期   页码 656-666 doi: 10.1007/s11708-021-0765-9

摘要： In recent years, defect-engineered Zr-based UiO-66 metal-organic frameworks (UiO-66(Zr) metal-organic frameworks (MOFs)) have shown huge advantages in catalytic, functional materials, adsorption, and other fields due to their large surface areas, well-ordered porous structures, and flexible tailorability. It is extremely challenging to introduce defect sites in the synthesis of MOFs to regulate the physicochemical properties of materials such as (energy band structure, pore structure, etc.) to obtain an excellent performance. This paper reviews the recent research results of synthesis methods, characterization technologies, and application fields of defect-engineered UiO-66(Zr) MOFs materials in order to provide new insights to synthesize high-performance UiO-66(Zr) MOFs materials and promote the development of UiO-66(Zr) in various fields.

关键词： defect engineering     metal-organic frameworks     UiO-66     photocatalysis    

HTML PDF 收藏

Special issue on the Asian Congress on Biotechnology 2011

Bang-Ce YE

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 125-125 doi: 10.1007/s11705-012-1291-4

HTML PDF 收藏

Microwave-assisted catalytic oxidation of gaseous toluene with a Cu-Mn-Ce/cordierite honeycomb catalyst

Longli Bo, Shaoyuan Sun

《化学科学与工程前沿（英文）》 2019年 第13卷 第2期   页码 385-392 doi: 10.1007/s11705-018-1738-3

摘要： A novel Cu-Mn-Ce/cordierite honeycomb catalyst was prepared by an incipient wetness method and the catalyst was characterized. The active ingredients were present as various spinel species of Cu, Mn and Ce oxides with different valences and they were unevenly dispersed over the surface of the catalyst. The catalytic oxidation of gaseous toluene was primarily investigated using a fixed bed reactor under microwave heating in the continuous flow mode. Under the optimal conditions of 6.7 wt-% loading of the active component, a bed temperature of 200°C, a flow rate of 0.12 m ·h and an initial concentration of toluene of 1000 mg·m , the removal and mineralization efficiencies of toluene were 98% and 70%, respectively. Thus the use of the microwave effectively improved the oxidation of toluene and this is attributed to dipole polarization and hotspot effects. After four consecutive cycles (a total of 1980 min), the Cu-Mn-Ce/cordierite catalyst still exhibited excellent catalytic activity and structural stability, and the toluene removal was higher than 90%. This work demonstrates the possibility of treating volatile organic compounds in exhaust gases by microwave-assisted catalytic oxidation.

关键词： microwave     catalytic oxidation     toluene     Cu-Mn-Ce/cordierite     mineralization    

HTML PDF 收藏

Reductive amination of -hexanol to -hexylamine over Ni–Ce/-AlO catalysts

《化学科学与工程前沿（英文）》 2023年 第17卷 第1期   页码 82-92 doi: 10.1007/s11705-022-2181-z

摘要： The amination of alkyl alcohols is one of the most promising paths in synthesis of aliphatic amines. Herein, cerium doped nickel-based catalysts were synthesized and tested in a gas-phase amination of n-hexanol to n-hexylamine. It was found that the activity of the Ni/γ-Al2O3 catalyst is significantly improved by doping an appropriate amount of cerium. The presence of cerium effectively inhibits the agglomeration of nickel particle, resulting in better Ni dispersion. As Ni particle size plays critical role on the catalytic activity, higher turnover frequency of n-hexanol amination was achieved. Cerium doping also improves the reduction ability of nickel and enhances the interactions between Ni and the catalyst support. More weak acid sites were also found in those cerium doped catalysts, which promote another key step—ammonia dissociative adsorption in this reaction system. The overall synergy of Ni nanoparticles and acid sites of this Ni–Ce/γ-Al2O3 catalyst boosts its superior catalytic performance in the amination of n-hexanol.

关键词： amination     alcohol     cerium     nickel     acidity     interaction    

HTML PDF 收藏

Effect of different acid anions on highly efficient Ce-based catalysts for selective catalytic reduction

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1399-1411 doi: 10.1007/s11705-023-2345-5

摘要： Three kinds of Ce-based catalysts (CePO4, CeVO4, Ce2(SO4)3) were synthesized and used for the selective catalytic reduction (SCR) of NO by NH3. NH3-SCR performances were conducted in the temperature range of 80 to 400 °C. The catalytic efficiencies of the three catalysts are as follow: CePO4 > CeVO4 > Ce2(SO4)3, which is in agreement with their abilities of NH3 adsorption capacities. The highest NO conversion rate of CePO4 could reach about 95%, and the catalyst had more than 90% NO conversion rate between 260 and 320 °C. The effect of PO43–, VO43– and SO42– on NH3-SCR performances of Ce-based catalysts was systematically investigated by the X-ray photoelectron spectroscopy analysis, NH3 temperature programmed desorption, H2 temperature programmed reduction and field emission scanning electron microscopy tests. The key factors that can enhance the SCR are the existence of Ce4+, large NH3 adsorption capacity, high and early H2 consumptions, and suitable microstructures for gas adsorption. Finally, CePO4 and CeVO4 catalysts also exhibited relatively strong tolerance of SO2, and the upward trend about 8% was detected due to the sulfation enhancement by SO2 for Ce2(SO4)3.

关键词： CePO4     CeVO4     Ce2(SO4)3     selective catalytic reduction     NO removal    

HTML PDF 收藏

Oxidation-extraction desulfurization of model oil over Zr-ZSM-5/SBA-15 and kinetic study

Chuanzhu LU,Hui FU,Huipeng LI,Hua ZHAO,Tianfeng CAI

《化学科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 203-211 doi: 10.1007/s11705-014-1420-3

摘要： ZSM-5/SBA-15 composite molecular sieves were synthesized using post-synthesis method and characterized by X-ray diffraction and N adsorption-desorption. The oxidative-extration desulfurization of model oil was investigated by using hydrogen peroxide as the oxidant, tetrabutyl ammonium bromide as phase transfer catalyst, dimethyl sulfoxide as extractant, and Zr-ZSM-5/SBA-15, Ag-ZSM-5/SBA-15, Ce-ZSM-5/SBA-15 as catalyst. Under the optimal conditions, the desulfurization rate decreases in the order: Zr-ZSM-5/SBA-15>Ce-ZSM-5/SBA-15>Ag-ZSM-5/SBA-15. The highest desulfurization rate is 84.53% under the catalysis of Zr-ZSM-5/SBA-15. Kinetics analysis shows that the reaction is pseudo-first-order with the activation energy of 44.23 kJ/mol.

关键词： composite molecular sieve     oxidation desulfuration     extraction     kinetic    

HTML PDF 收藏

标题 作者 时间 类型 操作

Preparation of ceria-zirconia solid solution with enhanced oxygen storage capacity and redox performance

Lijing MENG, Licheng LIU, Xuehong ZI, Hongxing DAI, Hong HE, Zhen ZHAO, Xinping WANG,

期刊论文

An investigation of the CHOH and CO selectivity of CO hydrogenation over Cu–Ce–Zr catalysts

期刊论文

PM-support interfacial effect and oxygen mobility in Pt, Pd or Rh-loaded (Ce,Zr,La)O catalysts

期刊论文

Tailoring the simultaneous abatement of methanol and NO on Sb-Ce-Zr catalysts via copper modification

期刊论文

The influence of the NCO/OH ratio and the 1,6-hexanediol/dimethylol propionic acid molar ratio on the

Jiao Feng, Qiuhao Lu, Weimin Tan, Kequan Chen, Pingkai Ouyang

期刊论文

Promotion of transition metal oxides on the NH

Weiman Li, Haidi Liu, Yunfa Chen

期刊论文

Cooperative effect between copper species and oxygen vacancy in CeZrCuO catalysts for carbon monoxide oxidation

期刊论文

Promoting effect of Zr on the catalytic combustion of methane over Pd/γ-Al

Hongbo NA,Tianle ZHU,Zhiming LIU,Yifei SUN

期刊论文

Modeling of Ce(IV) transport through a dispersion flat combined liquid membrane with carrier P507

Liang PEI,Liming WANG,Zhanying MA

期刊论文

Research progress of defect-engineered UiO-66(Zr) MOFs for photocatalytic hydrogen production

期刊论文

Special issue on the Asian Congress on Biotechnology 2011

Bang-Ce YE

期刊论文

Microwave-assisted catalytic oxidation of gaseous toluene with a Cu-Mn-Ce/cordierite honeycomb catalyst

Longli Bo, Shaoyuan Sun

期刊论文

Reductive amination of -hexanol to -hexylamine over Ni–Ce/-AlO catalysts

期刊论文

Effect of different acid anions on highly efficient Ce-based catalysts for selective catalytic reduction

期刊论文

Oxidation-extraction desulfurization of model oil over Zr-ZSM-5/SBA-15 and kinetic study

Chuanzhu LU,Hui FU,Huipeng LI,Hua ZHAO,Tianfeng CAI

期刊论文