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Catalytic activity of cerium-doped Ru/AlO during ozonation of dimethyl phthalate

ZHOU Yunrui, ZHU Wanpeng, CHEN Xun

《环境科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 354-357 doi: 10.1007/s11783-008-0059-z

摘要： In this paper, factors influencing the mineralization of dimethyl phthalate (DMP) during catalytic ozonation with a cerium-doped Ru/AlO catalyst were studied. The catalytic contribution was calculated through the results of a comparison experiment. It showed that doping cerium significantly enhanced catalytic activity. The total organic carbon (TOC) removal over the doped catalyst at 100 min reached 75.1%, 61.3% using Ru/AlO catalyst and only 14.0% using ozone alone. Catalytic activity reached the maximum when 0.2% of ruthenium and 1.0% of cerium were simultaneously loaded onto AlO support. Results of experiments on oxidation by ozone alone, adsorption of the catalyst, Ce ion’s and heterogeneous catalytic ozonation confirmed that the contribution of heterogeneous catalytic ozonation was about 50%, which showed the obvious effect of Ru–Ce/AlO on catalytic activity.

关键词： Ru–Ce/AlO     dimethyl phthalate     mineralization     comparison experiment     catalytic ozonation    

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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    

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Cu/Cr co-stabilization mechanisms in a simulated AlO-FeO-CrO-CuO waste system

《环境科学与工程前沿（英文）》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1408-4

摘要：

• Cu and Cr can be mostly incorporated into CuFexAlyCr2−x−yO4 with a spinel structure.

关键词： Spinel structure     Copper     Chromium     Co-stabilization     Thermal treatment    

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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)    

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Biopolymer-stabilized emulsions on the basis of interactions between β -lactoglobulin and ι -carrageenan

Qiaomei RU, Younghee CHO, Qingrong HUANG,

《化学科学与工程前沿（英文）》 2009年 第3卷 第4期   页码 399-406 doi: 10.1007/s11705-009-0253-y

摘要： -Carrageenan and -lactoglobulin (-lg) stabilized oil-in-water (O/W) emulsions, which can be used for the oral administration of bioactive but environmentally sensitive ingredients, have been successfully prepared. The effects of protein/polysaccharide ratios, total biopolymer concentration, environmental stress (thermal processing and sonication), and pH on the complex formation between -carrageenan and -lactoglobulin have been investigated. We found that -lactoglobulin and-carrageenan stabilized emulsions can be formed at pH values of 6.0, 4.0, and 3.4. However, the microstructures of emulsions stabilized by -lactoglobulin and -carrageenan was identified by optical microscopy, and it indicated that the emulsion prepared at pH 6.0 flocculated more extensively, while its hydrodynamic radius was much bigger than those prepared at pH 4.0 and 3.4. Regarding rheological properties, the emulsion of pH 6.0 showed a more solid-like behavior but with a lower viscosity than those of pH 4.0 and 3.4. The optimum concentration ranges for -lg and-carrageenan to form stable emulsions at pH 4.0 and 3.4 were 0.3wt-%―0.6wt-% and 0.4wt-%―0.7wt-%, respectively.
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Growth and properties analysis of metal-organic chemical vapor deposited MgZnO films on -AlO substrates

SHI Zengliang, LIU Dali, YAN Xiaolong, GAO Zhongmin, BAI Shiying

《机械工程前沿（英文）》 2008年 第3卷 第3期   页码 261-264 doi: 10.1007/s11465-008-0036-z

摘要： MgZnO (0 < ? 0.12) thin films with the wurtzite structure have been successfully grown on -AlO substrates by metal-organic chemical vapor deposition (MOCVD). X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), photoluminescence (PL) spectrometry, and transmission measurements are performed to study the characteristics of MgZnO thin films. Results show that with increasing Mg content, the diffraction peak of MgZnO thin films shifts towards a higher diffraction angle (the biggest shift is 0.22°), and the full width at half maximum (FWHM) of the diffraction peak is broadened. Meanwhile, a blue-shift occurs at the near-band-edge (NBE) emission peak and the largest blue-shift of the band gap of the MgZnO films is 113 meV with Mg content = 0.12. Therefore, the energy band gap of the MgZnO films is determined by Mg content in the thin films and the energy band gap increases with an increase of Mg content.

关键词： increase     photoelectron spectroscopy     transmission     wurtzite structure     MgZnO    

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Preparation of ultrafine α-AlO using precipitation-azeotropic distillation method

XIAO Jin, QIN Qi, ZHOU Feng, CHEN Yanbin, WAN Ye

《机械工程前沿（英文）》 2008年 第3卷 第2期   页码 226-231 doi: 10.1007/s11465-008-0029-y

摘要： Ammonium aluminum carbonate hydroxide (AACH) was prepared by a precipitation-azeotropic distillation method, which uses aluminum sulfate as the Al source and ammonium carbonate as the precipitant. Then, AACH was calcined into ultrafine ?-AlO powder. The factors that influence the dispersion property of ultrafine ?-AlO powder are discussed in this paper, such as the methods of adding materials, surfactant, and drying methods. The changes of the structure and property of ultrafine alumina in the thermal treatment process are also studied. The morphological structure and properties of AACH are characterized by DTA/TGA, SEM, XRD, and ICP measurements. The results show that ultrafine ?-AlO powder with a uniform particle size and well-distributed property can be synthesized only after aluminum sulfate atomizes into ammonium carbonate, proper amount of PEG1000 is added as the dispersant, and the product is treated by azeotropic distillation. The phase transformation of alumina during the calcination process can be described as amorphous AlO → ?-AlO → ?-AlO → ?-AlO. The crystal grain size and density of ultrafine alumina powder increase with the increase of the calcination temperature. After AACH has been calcined at 1200°C for 2 h, the ultrafine ?-AlO with uniform particle size, spherical shape, and more than 99.97% purity is obtained and its powder is well dispersed.

关键词： calcination temperature     spherical     AACH     carbonate hydroxide     ammonium carbonate    

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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

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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    

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Development of solid base catalyst X/Y/MgO/-AlO for optimization of preparation of biodiesel from L.seed

WANG Rui, YANG Song, YIN Shitao, SONG Baoan, BHADURY Pinaki S., XUE Wei, TAO Shuwei, JIA Zhaohui, LIU Da, GAO Liang

《化学科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 468-472 doi: 10.1007/s11705-008-0074-4

摘要： The preparation and regeneration conditions of the identified catalyst X/Y/MgO/-AlO with high catalytic activity were studied and optimized. The biodiesel was prepared by transesterification of seed oil produced in Guizhou with methanol at its reflux temoerature in the presence of X/Y/MgO/-AlO The pilot plant tests were carried out in a 100 L reaction vessel. Both average yield and fatty acid methyl esters (FAME) content reached more than 96.50% under the optimum reaction conditions of the pilot plant tests designed with an oil/methanol molar ratio of 1 : 10, catalyst concentration of 1.00%, and reaction time of 3 h at reflux temperature. In addition, analysis shows that the quality of biodiesel meets the standard EN 14214.

关键词： temperature     presence     addition     catalytic activity     catalyst X/Y/MgO/-AlO    

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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    

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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    

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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    

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Genetics of ischemic and hemorrhagic stroke in Chinese population

Wei-Li ZHANG MD, PhD, Ru-Tai HUI MD, PhD,

《医学前沿（英文）》 2010年 第4卷 第1期   页码 21-28 doi: 10.1007/s11684-010-0013-x

摘要： Stroke is a major cause of adult death and disability worldwide. Epidemiological and animal studies have provided strong evidence that the pathogenesis of stroke is multi-factorial and induced by a combination of environmental and genetic risk factors, but the identification of individual causative variants remains little known. Genetic influences are likely to be polygenic with small effect sizes, and stroke itself consists of a number of different subtypes which may each have different genetic profiles. In addition, various ethnic populations may have different stroke risk, such as Asian race. The reasons for high risk of stroke among the Chinese, especially hemorrhagic stroke, remain unknown. Most human studies have taken a candidate gene approach using case-control methodology. To be reliably detected, small relative risks require large sample sizes, probably 1000 patients or more. Genome-wide association (GWA) study is an unbiased and comprehensive approach to identify common risk alleles for complex diseases. Recently, a multistage GWA study has identified three loci on chromosomes 2q, 8q and 9p to be associated with intracranial aneurysm in European and Japanese populations. Another GWA finding is the identification of risk variants for cardioembolic stroke on chromosome 4q25 in European populations. In this review, we mainly focus on the results from case-control association studies on genetic factors that play a role in the risk of ischemic and hemorrhagic stroke in Chinese population. The combined effects of multiple susceptibility genes for stroke risk are also summarized.

关键词： genetics     ischemic stroke     hemorrhagic stroke     association study    

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Effects of La, Ce on nitrogen removal in sequencing batch reactor

Qing XIA , Rui LIANG , Yuning HONG , Lili DING , Hongqiang REN , Yuxiang MAO , Mingyu ZHAO ,

《环境科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 369-374 doi: 10.1007/s11783-009-0036-1

摘要： Batch experiments were conducted to study the short-term biological effects of rare earth ions (La, Ce) and their mixture on the nitrogen removal in a sequencing batch reactor (SBR). The data showed that higher NH―N removal rate, total inorganic nitrogen removal efficiency, and denitrification efficiency were achieved at lower concentrations of rare earth elements (REEs) (<1mg/L). In the first hour of the aeration stage of SBR, the presence of REEs increased the total inorganic nitrogen removal efficiency and NH―N removal efficiency by 15.7% and 10%―15%, respectively. When the concentrations of REEs were higher than 1mg/L, the total inorganic nitrogen removal efficiency decreased, and nitrate was found to accumulate in the effluent. When the concentrations of REEs was up to 50.0mg/L, the total inorganic nitrogen removal efficiency was less than 30% of the control efficiency with a high level of nitrate. Lower concentrations of REEs were found to accelerate the nitrogen conversion and removal in SBR.

关键词： rare earth     La3+     Ce3+     inorganic nitrogen     nitrogen removal     sequencing batch reactor    

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标题 作者 时间 类型 操作

Catalytic activity of cerium-doped Ru/AlO during ozonation of dimethyl phthalate

ZHOU Yunrui, ZHU Wanpeng, CHEN Xun

期刊论文

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

期刊论文

Cu/Cr co-stabilization mechanisms in a simulated AlO-FeO-CrO-CuO waste system

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

Biopolymer-stabilized emulsions on the basis of interactions between β -lactoglobulin and ι -carrageenan

Qiaomei RU, Younghee CHO, Qingrong HUANG,

期刊论文

Growth and properties analysis of metal-organic chemical vapor deposited MgZnO films on -AlO substrates

SHI Zengliang, LIU Dali, YAN Xiaolong, GAO Zhongmin, BAI Shiying

期刊论文

Preparation of ultrafine α-AlO using precipitation-azeotropic distillation method

XIAO Jin, QIN Qi, ZHOU Feng, CHEN Yanbin, WAN Ye

期刊论文

Special issue on the Asian Congress on Biotechnology 2011

Bang-Ce YE

期刊论文

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

期刊论文

Development of solid base catalyst X/Y/MgO/-AlO for optimization of preparation of biodiesel from L.seed

WANG Rui, YANG Song, YIN Shitao, SONG Baoan, BHADURY Pinaki S., XUE Wei, TAO Shuwei, JIA Zhaohui, LIU Da, GAO Liang

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

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

期刊论文

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

期刊论文

Genetics of ischemic and hemorrhagic stroke in Chinese population

Wei-Li ZHANG MD, PhD, Ru-Tai HUI MD, PhD,

期刊论文

Effects of La, Ce on nitrogen removal in sequencing batch reactor

Qing XIA , Rui LIANG , Yuning HONG , Lili DING , Hongqiang REN , Yuxiang MAO , Mingyu ZHAO ,

期刊论文