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期刊论文 73

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三塔悬索桥 2

9 %~12 % Cr 钢 1

&prime 1

&gamma 1

Al-Cr203体系 1

M23C6 碳化物 1

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

位移特征 1

偶氮苯 1

催化 1

六价铬 1

关键截面 1

分子开关 1

制备工艺 1

参数初值整定;自适应鲁棒控制;并联机构;气缸 1

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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    

An investigation of the CHOH and CO selectivity of CO hydrogenation over Cu–CeZr 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    

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    

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    

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    

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)    

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    

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)    

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    

Selective targeted adsorption and inactivation of antibiotic-resistant bacteria by Cr-loaded mixed metal

《环境科学与工程前沿(英文)》 2022年 第16卷 第6期 doi: 10.1007/s11783-021-1502-7

摘要:

• LDHs and MMOs was synthesized by ultrasound-assisted one-step co-precipitation.

关键词: Heavy metal adsorption     Magnetic hydrotalcite     ARBs removal     Cr(VI)-MMOs combined antibacterial activity    

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

The biosorption of Cr(VI) ions by dried biomass obtained from a chromium-resistant bacterium

Paul Fabrice NGUEMA,Zejiao LUO,Jingjing LIAN

《化学科学与工程前沿(英文)》 2014年 第8卷 第4期   页码 454-464 doi: 10.1007/s11705-014-1456-4

摘要: The biosorption potential of many different kinds of biomaterials has been widely studied. However, there is little data on the biosorption mechanism of Cr(VI) by dried biomass. So the bio-removal of Cr(VI) ions from aqueous solutions was investigated using dried biomass from a chromium-resistant bacterium. The bacterium was isolated from dewatered sludge samples that were obtained from a sewage treatment plant. Equilibrium and kinetic experiments were performed at different metal concentrations, pH values, and biosorbents dosages. The biomass was characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The functional groups in the biomass which may play a role in the biosorption process were identified by Fourier transform infrared spectroscopy. The biosorption process was found to be highly pH dependent and the optimum pH for the adsorption of Cr(VI) was 2.0±0.3 at 30±2 °C. The experimental data fit well with Langmuir and Freundlich models as well as a pseudo-second order kinetic model. The mechanism for the biosorption was also studied by fitting the kinetic data with an intra-particle diffusion model and a Boyd plot. External mass transfer was found to be the rate-determining step for the adsorption process. Biosorption could be an alternative mechanism besides bio-oxidation and bio-reduction for the bioremediation of heavy metals.

关键词: Cr(VI)     biomass     Bacillus cereus Pf-1     biosorption capacity     biosorbents    

Decontamination of Cr(VI) facilitated formation of persistent free radicals on rice husk derived biochar

Kaikai Zhang, Peng Sun, Yanrong Zhang

《环境科学与工程前沿(英文)》 2019年 第13卷 第2期 doi: 10.1007/s11783-019-1106-7

摘要:

PFRs were produced on biochar during Cr(VI) decontamination.

PFRs formation on biochar was owing to the oxidization of phenolic-OH by Cr(VI).

Appearance of excessive oxidant led to the consumption of PFRs on biochar.

Biochar charred at high temperature possessed great performance to Cr(VI) removal.

关键词: Biochar     Persistent free radicals     Phenolic hydroxyl groups     Cr(VI) reduction    

Hyperbranched magnetic polymer: highly efficient removal of Cr(VI) and application in electroplating

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1568-1580 doi: 10.1007/s11705-023-2303-2

摘要: By using a two-step hydrothermal method and trithiocyanuric acid (TTCA), 2,4,6-trihydrazino-1,3,5-triazine (THT), and Fe3O4 as raw materials, a spherical magnetic adsorbent polymer (TTCA/THT@Fe3O4) was synthesized to achieve the efficient removal of Cr(VI) from wastewater. Under optimal adsorption conditions, the maximum adsorption capacity of TTCA/THT@Fe3O4 for Cr(VI) can reach 1340 mg∙g‒1. Notably, the removal efficiency can approach 98.9%, even at the lower concentration of 20 mg∙L‒1 Cr(VI). For actual wastewater containing Cr(VI), the Cr(VI) concentration was reduced from 25.8 to 0.4 mg∙L‒1, a remarkable 20% lower than the current industry discharge standard value. A mechanism for the high adsorption performance of Cr(VI) on TTCA/THT@Fe3O4 was investigated using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and density functional theory. It can be plausibly attributed to the formation of Cr/N and Cr/S coordination bonds. Additionally, surface electrostatic adsorption, reduction effects, and the spherical polymer structure increase the contact area with Cr(VI), maximizing adsorption. The synergistic effect of adsorption and reduction enhances the adsorption performance of TTCA/THT@Fe3O4 for Cr(VI) and total chromium in water. The resultant polymer has a simple preparation process, excellent adsorption performance, easy magnetic separation, and promising application for actual wastewater.

关键词: magnetic polymer     chromium removal     hydrogen bonding     recyclability     actual wastewater    

Enhancement of extracellular Cr(VI) reduction for anammox recovery using hydrazine: performance, pathways

《环境科学与工程前沿(英文)》 2023年 第17卷 第9期 doi: 10.1007/s11783-023-1715-z

摘要:

● N2H4 addition enhanced and recovered anammox performance under Cr(VI) stress.

关键词: Extracellular Cr(VI) reduction     Electron transfer     Anammox     Hydrazine     Cr(VI) inhibition    

标题 作者 时间 类型 操作

Promotion of transition metal oxides on the NH

Weiman Li, Haidi Liu, Yunfa Chen

期刊论文

An investigation of the CHOH and CO selectivity of CO hydrogenation over Cu–CeZr 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

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

期刊论文

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

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

Selective targeted adsorption and inactivation of antibiotic-resistant bacteria by Cr-loaded mixed metal

期刊论文

Special issue on the Asian Congress on Biotechnology 2011

Bang-Ce YE

期刊论文

The biosorption of Cr(VI) ions by dried biomass obtained from a chromium-resistant bacterium

Paul Fabrice NGUEMA,Zejiao LUO,Jingjing LIAN

期刊论文

Decontamination of Cr(VI) facilitated formation of persistent free radicals on rice husk derived biochar

Kaikai Zhang, Peng Sun, Yanrong Zhang

期刊论文

Hyperbranched magnetic polymer: highly efficient removal of Cr(VI) and application in electroplating

期刊论文

Enhancement of extracellular Cr(VI) reduction for anammox recovery using hydrazine: performance, pathways

期刊论文