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Rh₂O₃/hexagonal CePO₄ nanocatalysts for N₂O decomposition

Huan Liu, Zhen Ma

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 586-593 doi: 10.1007/s11705-017-1659-6

摘要： Hexagonal CePO nanorods were prepared by a precipitation method and hexagonal CePO nanowires were prepared by hydrothermal synthesis at 150 °C. Rh(NO ) was then used as a precursor for the impregnation of Rh O onto these CePO materials. The Rh O supported on the CePO nanowires was much more active for the catalytic decomposition of N O than the Rh O supported on CePO nanorods. The stability of both catalysts as a function of time on stream was studied and the influence of the co-feed (CO , O , H O or O /H O) on the N O decomposition was also investigated. The samples were characterized by N adsorption-desorption, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, transmission electron microscopy, X-ray photoelectron microscopy, hydrogen temperature-programmed reduction, oxygen temperature-programmed desorption, and CO temperature-programmed desorption in order to correlate the physicochemical and catalytic properties.

关键词： Rh₂O₃ CePO₄ N₂O decomposition

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N₂O emission from a sequencing batch reactor for biological N and P removal from wastewater

Lei SHEN,Yuntao GUAN,Guangxue WU,Xinmin ZHAN

《环境科学与工程前沿（英文）》 2014年第8卷第5期页码 776-783 doi: 10.1007/s11783-013-0586-0

摘要： Nitrous oxide (N O) is a greenhouse gas that can be released during biological nitrogen removal from wastewater. N O emission from a sequencing batch reactor (SBR) for biological nitrogen and phosphorus removal from wastewater was investigated, and the aims were to examine which process, nitrification or denitrification, would contribute more to N O emission and to study the effects of heterotrophic activities on N O emission during nitrification. The results showed that N O emission was mainly attributed to nitrification rather than to denitrification. N O emission during denitrification mainly occurred with stored organic carbon as the electron donor. During nitrification, N O emission was increased with increasing initial ammonium or nitrite concentrations. The ratio of N O emission to the removed ammonium nitrogen (N O-N/NH -N) was 2.5% in the SBR system with high heterotrophic activities, while this ratio was in the range from 0.14% to 1.06% in batch nitrification experiments with limited heterotrophic activities.

关键词： biological nutrient removal denitrification greenhouse gas nitrification nitrous oxide

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Persulfate-induced three coordinate nitrogen (N3C) vacancies in defective carbon nitride for enhancedphotocatalytic H2O2 evolution

Wei Miao,Yijie Wang,Ying Liu,Hehe Qin,Chengcheng Chu,Shun Mao,

《工程（英文）》 doi: 10.1016/j.eng.2021.12.016

摘要： In-situ photocatalytic H2O2 production has been receiving increasing attention in recent years for sustainable H2O2 synthesis. Graphitic carbon nitride (g-C3N4) is regarded as one of the most promising semiconductor photocatalysts for H2O2 evolution. Introducing N defects in g-C3N4 has been proved to be an effective strategy to enhance photocatalytic activity. However, the photocatalytic mechanism of the N vacancies is ambiguous and different types of N vacancies in g-C3N4 may exhibit different effects on photocatalytic activity. Herein, we develop a facile sodium persulfate eutectic polymerization method to prepare the g-C3N4 with abundant three coordinate nitrogen (N3C) vacancies. This type of nitrogen vacancy has not been studied in g-C3N4 for photocatalytic H2O2 production. Our results showed that the introduction of N3C vacancies in the g-C3N4 successfully broadened the light absorption range, inhibited the photoexcited charge recombination with enhanced O2 adsorption to promote oxygen activation. The photocatalytic H2O2 evolution from the N3C-rich g-C3N4 is 4.5 times higher than that of the pristine g-C3N4. This study demonstrates a novel strategy to introduce N3C vacancies in g-C3N4, which offers a new method to develop active catalysts for photocatalytic H2O2 evolution.Graphical abstractDownload : Download high-res image (60KB)Download : Download full-size image

关键词： Carbon nitride N3 C vacancy Hydrogen peroxide evolution Photocatalysis Persulfate

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CH₄ and N₂O emissions from double-rice cropping system as affected by Chinese milk

Heshui XU,Dengyun LI,Bo ZHU,Kai ZHANG,Yadong YANG,Chen WANG,Ying JIANG,Zhaohai ZENG

《农业科学与工程前沿（英文）》 2017年第4卷第1期页码 59-68 doi: 10.15302/J-FASE-2017137

摘要： Chinese milk vetch (CMV) and rice straw (RS) were incorporated into soil to substitute for synthetic N fertilizers and to maintain soil fertility. However, little is known about the integrated impacts of CMV and RS incorporation on CH and N O emissions in double-rice cropping systems in southern China. A field experiment was conducted to estimate the integrated impacts of CMV and RS incorporation in the early- and late-rice seasons on CH and N O emissions. All treatments received uniform N inputs, 6%–37% of which was replaced by CMV and RS crop residue. CMV and/or RS incorporation produced equivalent or slightly more grain yield, while reducing N O emissions by 3%–43%. However, both CMV and RS incorporation increased CH emissions. Annual CH emissions ranged from 321 to 614 kg·hm from CMV and RS amendment treatments, which were 1.5–2.9 times higher than that from synthetic N. Compared with single synthetic N fertilizer, incorporation of CMV and/or RS increased GWP and yield-scaled GWP by 45%–164% and 45%–153%, respectively. Our results demonstrate CMV and RS amendments replacing N fertilizer, maintained stable yield, mitigated N O emission, but enhanced CH emission. Further study is needed on crop residue management in double-cropping rice systems.

关键词： Chinese milk vetch CH₄ double-rice cropping system grain yield N₂O rice straw

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Production of N

Youkui GONG,Yongzhen PENG,Shuying WANG,Sai WANG

《环境科学与工程前沿（英文）》 2014年第8卷第4期页码 589-597 doi: 10.1007/s11783-013-0571-7

摘要： The N O production in two nitrogen removal processes treating domestic wastewater was investigated in laboratory-scale aerobic-anoxic sequencing batch reactors (SBRs). Results showed that N O emission happened in the aerobic phase rather than in the anoxic phase. During the aerobic phase, the nitrogen conversion to N O gas was 27.7% and 36.8% of loss for conventional biologic N-removal process and short-cut biologic N-removal process. The dissolved N O was reduced to N in the anoxic denitrification phase. The N O production rate increased with the increasing of nitrite concentration and ceased when oxidation was terminated. Higher nitrite accumulation resulted in higher N O emission in the short-cut nitrogen removal process. Pulse-wise addition of 20 mg gave rise to 3-fold of N O emission in the conventional N-removal process, while little change happened with 20 mg was added to SBR1.

关键词： conventional N-removal process N₂O short-cut N-removal process nitrite accumulation ammonia- oxidizing bacteria (AOB) denitrification

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The performance of nitrate-reducing Fe(II) oxidation processes under variable initial Fe/N ratios: The

《环境科学与工程前沿（英文）》 2021年第15卷第4期 doi: 10.1007/s11783-020-1366-2

摘要：

•Bacterially-mediated coupled N and Fe processes examined in incubation experiments.

关键词： Denitrification N₂O emission Fe(II) oxidation Fe/N ratio Fe minerals

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基于开关型活性Al₂O₃纳米颗粒稳定的新型CO₂/N₂响应型Pickering乳液 Article

陈安, 王朵, 陈静思, 徐建鸿, 曾宏波

《工程（英文）》 2022年第12卷第5期页码 48-54 doi: 10.1016/j.eng.2020.08.031

摘要：

本文报道了一种新型开关型Pickering乳液，这种乳液具有快速的CO₂/N₂响应能力，可以通过静电作用使氧化铝纳米颗粒与微量的开关型超亲合剂进行原位疏水稳定在引入CO₂ 30 s 后，Pickering乳液可以自发地破乳化，并实现完全的相分离；然后乳液可以在N₂吹扫10 min后的均质化过程中得到重构。开关型Pickering乳液的CO₂/N₂响应行为归因于在CO₂或N₂交替鼓泡时，开关型表面活性剂在氧化铝纳米颗粒表面的可逆的解吸由于表面活性剂的制造简便性和氧化铝纳米颗粒的疏水性，本研究开发了一种极其简便且具有成本效益的方法，用于制备可快速响应CO₂/N₂的开关型Pickering 乳液此外，所制备的具有CO₂/N₂响应能力的开关型Pickering乳液对环境友好、温和、无毒；因此，该乳液具有巨大的实际应用潜力，并且具有可观的经济和环境效益，

关键词： CO₂/N₂刺激响应 Pickering乳液开关型表面活性剂氧化铝纳米颗粒超两亲化合物

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Effects of Pd doping on N

Mingxin Dong, Jun Wang, Jinxin Zhu, Jianqiang Wang, Wulin Wang, Meiqing Shen

《环境科学与工程前沿（英文）》 2017年第11卷第6期 doi: 10.1007/s11783-017-0976-9

摘要： N O is a powerful greenhouse gas and plays an important role in destructing the ozone layer. This present work investigated the effects of Pd doping on N O formation over Pt/BaO/Al O catalyst. Three types of catalysts, Pt/BaO/Al O , Pt/Pd mechanical mixing catalyst (Pt/BaO/Al O +Pd/Al O ) and Pt-Pd co-impregnation catalyst (Pt-Pd/BaO/Al O ) were prepared by incipient wetness impregnation method. These catalysts were first evaluated in NSR activity tests using H /CO as reductants and then carefully characterized by BET, CO chemisorption, CO-DRIFTs and H -TPR techniques. In addition, temperature programmed reactions of NO with H /CO were conducted to obtain further information about N O formation mechanism. Compared with Pt/BaO/Al O , (Pt/BaO/Al O +Pd/Al O ) produced less N O and more NH during NO storage and reduction process, while an opposite trend was found over (Pt-Pd/BaO/Al O +Al O ). Temperature programmed reactions of NO with H /CO results showed that Pd/Al O component in (Pt/BaO/Al O +Pd/Al O ) played an important role in NO reduction to NH , and the formed NH could reduce NO to N leading to a decrease in N O formation. Most of N O formed over (Pt-Pd/BaO/Al O +Al O ) was originated from Pd/BaO/Al O component. H -TPR results indicated Pd-Ba interaction resulted in more difficult-to-reduce PdO species over Pd/BaO/Al O , which inhibits the NO dissociation and thus drives the selectivity to N O in NO reduction.

关键词： NO_x storage reduction Pt/BaO/Al₂O₃ Pd doping N₂O formation Optimization

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Physical and chemical processes of wintertime secondary nitrate aerosol formation

Qi YING

《环境科学与工程前沿（英文）》 2011年第5卷第3期页码 348-361 doi: 10.1007/s11783-011-0343-1

摘要： The UCD/CIT model was modified to include a process analysis (PA) scheme for gas and particulate matter (PM) to study the formation of secondary nitrate aerosol during a stagnant wintertime air pollution episode during the California Regional PM /PM Air Quality Study (CRPAQS) where detailed measurements of PM components are available at a few sites. Secondary nitrate is formed in the urban areas from near the ground to a few hundred meters above the surface during the day with a maximum modeled net increase rate of 4 μg·m ·d during the study episode. The secondary nitrate formation rate in rural areas is lower due to lower NO . In the afternoon hours, near-surface temperature can be high enough to evaporate the particulate nitrate. In the nighttime hours, both the gas phase N O reactions with water vapor and the N O heterogeneous reactions with particle-bound water are important for secondary nitrate formation. The N O reactions are most import near the surface to a few hundred meters above surface with a maximum modeled net secondary nitrate increase rate of 1 μg·m ·d and are more significant in the rural areas where the O concentrations are high at night. In general, vertical transport during the day moves the nitrate formed near the surface to higher elevations. During the stagnant days, process analysis indicates that the nitrate concentration in the upper air builds up and leads to a net downward flux of nitrate through vertical diffusion and a rapid increase of surface nitrate concentration.

关键词： secondary nitrate aerosol N₂O₅ heterogeneous reaction process analysis

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NiCoO@quinone-rich N–C core–shell nanowires as composite electrode for electric double layer capacitor

《化学科学与工程前沿（英文）》 doi: 10.1007/s11705-022-2223-6

摘要： The bind-free carbon cloth-supported electrodes hold the promises for high-performance electrochemical capacitors with high specific capacitance and good cyclic stability. Considering the close connection between their performance and the amount of carbon material loaded on the electrodes, in this work, NiCo₂O₄ nanowires were firstly grown on the substrate of active carbon cloth to provide the necessary surface area in the longitudinal direction. Then, the quinone-rich nitrogen-doped carbon shell structure was formed around NiCo₂O₄ nanowires, and the obtained composite was used as electrode for electric double layer capacitor. The results showed that the composite electrode displayed an area-specific capacitance of 1794 mF∙cm^–2 at the current density of 1 mA∙cm^–2. The assembled symmetric electric double layer capacitor achieved a high energy density of 6.55 mW∙h∙cm^–3 at a power density of 180 mW∙cm^–3. The assembled symmetric capacitor exhibited a capacitance retention of 88.96% after 10000 charge/discharge cycles at the current density of 20 mA∙cm^–2. These results indicated the potentials in the preparation of the carbon electrode materials with high energy density and good cycling stability.

关键词： carbon cloth NiCo₂O₄ nanowires core−shell structure quinone-rich electric double layer capacitor

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Hydroxyl radical intensified Cu

Wenyue Li, Min Chen, Zhaoxiang Zhong, Ming Zhou, Weihong Xing

《环境科学与工程前沿（英文）》 2020年第14卷第6期 doi: 10.1007/s11783-020-1281-6

摘要： Abstract • Cu2O NPs/H2O2 Fenton process was intensified by membrane dispersion. • DMAc removal was enhanced to 98% for initial DMAc of 14000 mg/L. • Analyzed time-resolved degradation pathway of DMAc under ·OH attack. High-concentration industrial wastewater containing N,N-dimethylacetamide (DMAc) from polymeric membrane manufacturer was degraded in Cu2O NPs/H2O2 Fenton process. In the membrane-assisted Fenton process DMAc removal rate was up to 98% with 120 min which was increased by 23% over the batch reactor. It was found that ·OH quench time was extended by 20 min and the maximum ·OH productivity was notably 88.7% higher at 40 min. The degradation reaction rate constant was enhanced by 2.2 times with membrane dispersion (k = 0.0349 min−1). DMAc initial concentration (C0) and H2O2 flux (Jp) had major influence on mass transfer and kinetics, meanwhile, membrane pore size (rp) and length (Lm) also affected the reaction rate. The intensified radical yield, fast mass transfer and nanoparticles high activity all contributed to improve pollutant degradation efficiency. Time-resolved DMAc degradation pathway was analyzed as hydroxylation, demethylation and oxidation leading to the final products of CO2, H2O and NO3− (rather than NH3 from biodegradation). Continuous process was operated in the dual-membrane configuration with in situ reaction and separation. After five cycling tests, DMAc removal was all above 95% for the initial [DMAc]0 = 14,000 mg/L in wastewater and stability of the catalyst and the membrane maintained well.

关键词： Ceramic membrane reactor N N-dimethylacetamide Fenton process Cu₂O Wastewater treatment

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Phylogenetic diversity of NO reductases, new tools for monitoring, and insights into NO production in natural and engineered environments

《环境科学与工程前沿（英文）》 2022年第16卷第10期 doi: 10.1007/s11783-022-1562-3

摘要：

● 548 representative nor genes were collected to create complete phylogenetic trees.

关键词： N₂O Greenhouse gas NO reductase NO dismutase Primer Crystal structure

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New insight into effect of potential on degradation of Fe-N-C catalyst for ORR

Yanyan GAO, Manman QI, Liang HE, Haiping CHEN, Wenzhe LUO, Ming HOU, Zhigang SHAO

《能源前沿（英文）》 2021年第15卷第2期页码 421-430 doi: 10.1007/s11708-021-0727-2

摘要： In recent years, Fe-N-C catalyst is particularly attractive due to its high oxygen reduction reaction (ORR) activity and low cost for proton exchange membrane fuel cells (PEMFCs). However, the durability problems still pose challenge to the application of Fe-N-C catalyst. Although considerable work has been done to investigate the degradation mechanisms of Fe-N-C catalyst, most of them are simply focused on the active-site decay, the carbon oxidation, and the demetalation problems. In fact, the 2e pathway in the ORR process of Fe-N-C catalyst would result in the formation of H O , which is proved to be a key degradation source. In this paper, a new insight into the effect of potential on degradation of Fe-N-C catalyst was provided by quantifying the H O intermediate. In this case, stability tests were conducted by the potential-static method in O saturated 0.1 mol/L HClO . During the tests, H O was quantified by rotating ring disk electrode (RRDE). The results show that compared with the loading voltage of 0.4 V, 0.8 V, and 1.0 V, the catalysts being kept at 0.6 V exhibit a highest H O yield. It is found that it is the combined effect of electrochemical oxidation and chemical oxidation (by aggressive radicals like H O /radicals) that triggered the highest H O release rate, with the latter as the major cause.

关键词： proton exchange membrane fuel cells (PEMFCs) oxygen reduction reaction (ORR) Fe-N-C catalyst potential H₂O₂ degradation

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Inexpensive synthesis of a high-performance Fe

Nadir Abbas, Godlisten N. Shao, Syed M. Imran, Muhammad S. Haider, Hee Taik Kim

《化学科学与工程前沿（英文）》 2016年第10卷第3期页码 405-416 doi: 10.1007/s11705-016-1579-x

摘要： A sol-gel technique has been developed for the synthesis of a magnetite-silica-titania (Fe O -SiO -TiO ) tertiary nanocomposite with improved photocatalytic properties based on the use of inexpensive titania and silica precursors. The exceptional photocatalytic activity of the resulting materials was demonstrated by using them to photocatalyze the degradation of methylene blue solution. The best formulation achieved 98% methylene blue degradation. An interesting feature of the present work was the ability to magnetically separate and reuse the catalyst. The efficiency of the catalyst remained high during two reuses. The synthesized nanomaterials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, ultra-violet-visible spectroscopy, diffuse reflectance spectroscopy, and thermogravimetric analysis. XRD analysis revealed the formation of multicrystalline systems of cubic magnetite and anatase titania crystals. SEM and TEM characterization revealed well-developed and homogeneously dispersed particles of size less than 15 nm. FTIR spectra confirmed the chemical interaction of titania and silica. It was further noticed that the optical properties of the prepared materials were dependent on the relative contents of their constituent metal oxides.

关键词： sol-gel photocatalysis magnetic recovery TiO₂ Fe₃O₄ SiO₂

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Pest management with biopesticides

James N. SEIBER, Joel COATS, Stephen O. DUKE, Aaron D. GROSS

《农业科学与工程前沿（英文）》 2018年第5卷第3期页码 295-300 doi: 10.15302/J-FASE-2018238

摘要：

Biopesticides are attracting interest as alternatives to conventional pesticides but without many of the non-target effects, promising a better record of safety and sustainability in pest control practices. In this article we summarize and discuss the current status and future promise of biopesticides, including how biopesticides use may increase the quality and safety of the food supply.

关键词： biopesticide GMO crops pest management

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标题作者时间类型操作

Rh₂O₃/hexagonal CePO₄ nanocatalysts for N₂O decomposition

Huan Liu, Zhen Ma

期刊论文

N₂O emission from a sequencing batch reactor for biological N and P removal from wastewater

Lei SHEN,Yuntao GUAN,Guangxue WU,Xinmin ZHAN

期刊论文

Persulfate-induced three coordinate nitrogen (N3C) vacancies in defective carbon nitride for enhancedphotocatalytic H2O2 evolution

Wei Miao,Yijie Wang,Ying Liu,Hehe Qin,Chengcheng Chu,Shun Mao,

期刊论文

CH₄ and N₂O emissions from double-rice cropping system as affected by Chinese milk

Heshui XU,Dengyun LI,Bo ZHU,Kai ZHANG,Yadong YANG,Chen WANG,Ying JIANG,Zhaohai ZENG

期刊论文

Production of N

Youkui GONG,Yongzhen PENG,Shuying WANG,Sai WANG

期刊论文

The performance of nitrate-reducing Fe(II) oxidation processes under variable initial Fe/N ratios: The

期刊论文

基于开关型活性Al₂O₃纳米颗粒稳定的新型CO₂/N₂响应型Pickering乳液

陈安, 王朵, 陈静思, 徐建鸿, 曾宏波

期刊论文

Effects of Pd doping on N

Mingxin Dong, Jun Wang, Jinxin Zhu, Jianqiang Wang, Wulin Wang, Meiqing Shen

期刊论文

Physical and chemical processes of wintertime secondary nitrate aerosol formation

Qi YING

期刊论文

NiCoO@quinone-rich N–C core–shell nanowires as composite electrode for electric double layer capacitor

期刊论文

Hydroxyl radical intensified Cu

Wenyue Li, Min Chen, Zhaoxiang Zhong, Ming Zhou, Weihong Xing

期刊论文

Phylogenetic diversity of NO reductases, new tools for monitoring, and insights into NO production in natural and engineered environments

期刊论文

New insight into effect of potential on degradation of Fe-N-C catalyst for ORR

Yanyan GAO, Manman QI, Liang HE, Haiping CHEN, Wenzhe LUO, Ming HOU, Zhigang SHAO

期刊论文

Inexpensive synthesis of a high-performance Fe

Nadir Abbas, Godlisten N. Shao, Syed M. Imran, Muhammad S. Haider, Hee Taik Kim

期刊论文

Pest management with biopesticides

James N. SEIBER, Joel COATS, Stephen O. DUKE, Aaron D. GROSS

期刊论文

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