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期刊论文 36

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三塔悬索桥 2

MIMO雷达；波形设计；谱分解；分式二次约束二次规划 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

二氧化碳 1

二肽基肽酶4 1

位移特征 1

偶氮苯 1

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参数初值整定；自适应鲁棒控制；并联机构；气缸 1

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发展路线图 1

受控核聚变 1

多传感器融合；障碍物检测；野外环境；智能车；无人驾驶地面车辆 1

多尺度模拟 1

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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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Vanadium(IV) solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with

《化学科学与工程前沿（英文）》 2023年 第17卷 第1期   页码 56-67 doi: 10.1007/s11705-022-2185-8

摘要： Separation of vanadium from black shale leaching solution at low pH is very meaningful, which can effectively avoid the generation of alkali neutralization slag and the resulting vanadium loss. In this study, coordination mechanism of vanadium in acid leaching solution at low pH was investigated with the intervention of chloride ions. Under the conditions of pH 0.8, di-(2-ethylhexyl)phosphoric acid concentration of 20%, phase ratio of 1:2, and extraction time of 8 min, the vanadium extraction could reach 80.00%. The Fourier transform infrared and electrospray ionization results reveal that, despite the fact that the chloride ion in the leachate could significantly promote vanadium extraction, the chloride ion does not enter the organic phase, indicating an intriguing phenomenon. Among Cl−–V, SO42−–V, and H2O–V, the V–Cl bond is longer and the potential difference between coordinate ions and vanadium is smaller. Therefore, VO2+ gets easily desorbed with chloride ions and enter the organic phase. At the same time, the hydrogen ions of di-(2-ethylhexyl)phosphoric acid also enter the water phase more easily, which reduces the pH required for the extraction reaction.

关键词： vanadium     black shale     solvent extraction     high acidity extraction    

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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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Astragaloside IV suppresses post-ischemic natural killer cell infiltration and activation in the brain

Baokai Dou, Shichun Li, Luyao Wei, Lixin Wang, Shiguo Zhu, Zhengtao Wang, Zunji Ke, Kaixian Chen, Zhifei Wang

《医学前沿（英文）》 2021年 第15卷 第1期   页码 79-90 doi: 10.1007/s11684-020-0783-8

摘要： Natural killer (NK) cells, a type of cytotoxic lymphocytes, can infiltrate into ischemic brain and exacerbate neuronal cell death. Astragaloside IV (ASIV) is the major bioactive ingredient of , a Chinese herbal medicine, and possesses potent immunomodulatory and neuroprotective properties. This study investigated the effects of ASIV on post-ischemic brain infiltration and activation of NK cells. ASIV reduced brain infarction and alleviated functional deficits in MCAO rats, and these beneficial effects persisted for at least 7 days. Abundant NK cells infiltrated into the ischemic hemisphere on day 1 after brain ischemia, and this infiltration was suppressed by ASIV. Strikingly, ASIV reversed NK cell deficiency in the spleen and blood after brain ischemia. ASIV inhibited astrocyte-derived CCL2 upregulation and reduced CCR2 NK cell levels in the ischemic brain. Meanwhile, ASIV attenuated NK cell activating receptor NKG2D levels and reduced interferon-γ production. ASIV restored acetylation of histone H3 and the p65 subunit of nuclear factor-κB in the ischemic brain, suggesting inhibition of histone deacetylase (HDAC). Simultaneously, ASIV prevented p65 nuclear translocation. The effects of ASIV on reducing CCL2 production, restoring acetylated p65 levels and preventing p65 nuclear translocation were mimicked by valproate, an HDAC inhibitor, in astrocytes subjected to oxygen-glucose deprivation. Our findings suggest that ASIV inhibits post-ischemic NK cell brain infiltration and activation and reverses NK cell deficiency in the periphery, which together contribute to the beneficial effects of ASIV against brain ischemia. Furthermore, ASIV’s effects on suppressing NK cell brain infiltration and activation may involve HDAC inhibition.

关键词： astragaloside IV     brain ischemia     natural killer cells     histone deacetylase     nuclear factor-κB    

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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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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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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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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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Visible light induces bacteria to produce superoxide for manganese oxidation

《环境科学与工程前沿（英文）》 2023年 第17卷 第2期 doi: 10.1007/s11783-023-1619-y

摘要：

● Term of manganese-oxidizing microorganisms should be reconsidered.

关键词： Mn(II) oxidation     Manganese-oxidizing bacteria     Reactive oxygen species     Mn(III/IV) oxides    

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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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Catalytic performance of Co-Mo-Ce-K/γ-Al

Yuqiong ZHAO, Yongfa ZHANG

《化学科学与工程前沿（英文）》 2010年 第4卷 第4期   页码 457-460 doi: 10.1007/s11705-010-0524-7

摘要： The catalytic performance of Co-Mo-Ce-K/γ-Al O catalyst for the shift reaction of CO in coke oven gas is investigated using X-ray diffraction (XRD) and temperature-programmed reduction (TPR). The results indicate that Ce and K have a synergistic effect on promoting the catalytic activity, and the Co-Mo-Ce-K/γ-Al O catalyst with 3.0 wt-% CeO and 6.0 wt-% K O exhibits the highest activity. CeO favors Co dispersion and mainly produces an electronic effect. TPR characterization results indicate that the addition of CeO -K O in the Co-Mo-Ce-K/γ-Al O catalyst decreases the reduction temperature of active components, and part of octahedrally coordinated Mo transforms into tetrahedrally coordinated Mo , which has a close relationship with the catalytic activity.

关键词： coke oven gas     water gas shift reaction     sulfur-tolerant catalyst     cerium dioxide    

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Principle and curve of planetary indexing cam mechanisms

LIU Ming-tao, ZHANG Ce, YANG Yu-hu

《机械工程前沿（英文）》 2006年 第1卷 第4期   页码 475-478 doi: 10.1007/s11465-006-0063-6

摘要： A new type of planetary indexing cam mechanism called type !c is presented. The transmission principle of type !c is discussed. Based on the principle of formation of conjugate tooth contour, the equations of the cam s pitch curve are derived. The continuity and symmetry of the cam s pitch curve are also analyzed. It can be concluded that: 1) This type has no output institution so the output precision can be improved; 2) The asymmetrical two-ring structure is used to overcome dead point and its phase angle is equal to (π - 2π/n); 3) The continuous condition of the cam s pitch curve is that the average transmission ratio is -n in an intermittent motion period.

关键词： continuity     planetary     average transmission     symmetry     intermittent    

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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    

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嫦娥1号卫星微波探月技术机理和应用研究

姜景山,王振占,李芸

《中国工程科学》 2008年 第10卷 第6期   页码 16-22

摘要：

微波探测仪是嫦娥1号卫星有效载荷之一，主要用于测量不同深度的月壤微波辐射亮温，进而反演月壤厚度的信息并对月球的3He资源量和分布进行评估。这是国际上第一次利用被动微波遥感探测器在月球轨道直接测量月表亮温信息。因此，对月壤辐射传输模型的研究是及其必要的。文章分析了月球微波探测的机理和存在的问题，并给出了初步解决途径。

关键词： 嫦娥1号微波探测仪     遥感     月壤     微波辐射传输    

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标题 作者 时间 类型 操作

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

Vanadium(IV) solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with

期刊论文

Special issue on the Asian Congress on Biotechnology 2011

Bang-Ce YE

期刊论文

Astragaloside IV suppresses post-ischemic natural killer cell infiltration and activation in the brain

Baokai Dou, Shichun Li, Luyao Wei, Lixin Wang, Shiguo Zhu, Zhengtao Wang, Zunji Ke, Kaixian Chen, Zhifei 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

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

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

Visible light induces bacteria to produce superoxide for manganese oxidation

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

Catalytic performance of Co-Mo-Ce-K/γ-Al

Yuqiong ZHAO, Yongfa ZHANG

期刊论文

Principle and curve of planetary indexing cam mechanisms

LIU Ming-tao, ZHANG Ce, YANG Yu-hu

期刊论文

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

期刊论文

嫦娥1号卫星微波探月技术机理和应用研究

姜景山,王振占,李芸

期刊论文