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δN-stable isotope analysis of NH: An overview on analytical measurements, source sampling and its source

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1414-6

摘要:

• Challenges in sampling of NH3 sources for d15N analysis are highlighted.

关键词: Aerosol ammonium     Atmospheric gaseous ammonia     Isotope fingerprinting     Isotope-based source apportionment     Ammonia gas-to-particle conversion    

Nitrogen pollution and source identification of urban ecosystem surface water in Beijing

Yufen REN, Zhiwei XU, Xinyu ZHANG, Xiaoke WANG, Xiaomin SUN, D. J. BALLANTINE, Shengzhong WANG

《环境科学与工程前沿(英文)》 2014年 第8卷 第1期   页码 106-116 doi: 10.1007/s11783-012-0474-z

摘要: Nitrogen contamination of surface water is a worldwide environmental problem with intensive agriculture and high population densities. We assessed the spatial and seasonal variation in concentrations of total nitrogen and different nitrogen species present in surface-water in Beijing, China. Also, chemical ( ) and isotopic ( ) indicators were used to identify nitrate sources. The results showed that, during 2009 and 2010, nitrate nitrogen concentrations ranged from 0.7 to 7.6 mg·L , ammonium nitrogen from 0.1 to 3.4 mg·L , and total nitrogen from 2.4 to 17.0 mg·L . Inorganic nitrogen accounted for between 60 and 100% of total nitrogen at the ten monitoring sites. Nitrate nitrogen, ammonium nitrogen, and total nitrogen concentrations at the 2 downstream monitoring sites in south-eastern Beijing were significantly higher than those at the other eight upstream monitoring sites ( <0.01). Examination of seasonal variation showed that there was a significant inverse relationship between nitrate nitrogen concentrations and precipitation, and that nitrate nitrogen concentrations peaked in the dry seasons. The information given by the values and nitrate nitrogen concentrations, combined with the ratio distribution, showed that domestic sewage was the major source of nitrate in Beijing. Methods to control and reduce sewage pollution are urgently needed to help manage surface water quality in Beijing.

关键词: nitrogen concentration     spatial and seasonal variation     stable nitrogen isotope     urban ecosystem     source    

communities biostimulated by ethanol during uranium (VI) bioremediation in contaminated sediment as shown by stableisotope probing

Mary Beth LEIGH,Wei-Min WU,Erick CARDENAS,Ondrej UHLIK,Sue CARROLL,Terry GENTRY,Terence L. MARSH,Jizhong ZHOU,Philip JARDINE,Craig S. CRIDDLE,James M. TIEDJE

《环境科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 453-464 doi: 10.1007/s11783-014-0721-6

摘要: Stable isotope probing (SIP) was used to identify microbes stimulated by ethanol addition in microcosms containing two sediments collected from the bioremediation test zone at the US Department of Energy Oak Ridge site, TN, USA. One sample was highly bioreduced with ethanol while another was less reduced. Microcosms with the respective sediments were amended with C labeled ethanol and incubated for 7 days for SIP. Ethanol was rapidly converted to acetate within 24 h accompanied with the reduction of nitrate and sulfate. The accumulation of acetate persisted beyond the 7 d period. Aqueous U did not decline in the microcosm with the reduced sediment due to desorption of U but continuously declined in the less reduced sample. Microbial growth and concomitant C-DNA production was detected when ethanol was exhausted and abundant acetate had accumulated in both microcosms. This coincided with U(VI) reduction in the less reduced sample. C originating from ethanol was ultimately utilized for growth, either directly or indirectly, by the dominant microbial community members within 7 days of incubation. The microbial community was comprised predominantly of known denitrifiers, sulfate-reducing bacteria and iron (III) reducing bacteria including , , , and others, including the known U(VI)-reducing bacteria A , and The findings suggest that ethanol biostimulates the U(VI)-reducing microbial community by first serving as an electron donor for nitrate, sulfate, iron (III) and U(VI) reduction, and acetate which then functions as electron donor for U(VI) reduction and carbon source for microbial growth.

关键词: Stable isotope probing (SIP)     ethanol     acetate     uranium reduction     sediment     bioremediation    

Determination of 27 pharmaceuticals and personal care products (PPCPs) in water: The benefit of isotope

Xueqi Fan, Jie Gao, Wenchao Li, Jun Huang, Gang Yu

《环境科学与工程前沿(英文)》 2020年 第14卷 第1期 doi: 10.1007/s11783-019-1187-3

摘要: • Isotope dilution method was developed for the determination of 27 PPCPs in water. • The established method was successfully applied to different types of water samples. • The correction effect of corresponding 27 ILSs over 70 d was investigated. • Benefit of isotopic dilution method was illustrated for three examples. Pharmaceuticals and personal care products (PPCPs) are a unique group of emerging and non-persistent contaminants. In this study, 27 PPCPs in various water samples were extracted by solid phase extraction (SPE), and determined by isotope dilution method using liquid chromatography coupled to tandem triple quadruple mass spectrometer (LC-MS/MS). A total of 27 isotopically labeled standards (ILSs) were applied to correct the concentration of PPCPs in spiked ultrapure water, drinking water, river, effluent and influent sewage. The corrected recoveries were 73%–122% with the relative standard deviation (RSD)<16%, except for acetaminophen. The matrix effect for all kinds of water samples was<22% and the method quantitation limits (MQLs) were 0.45–8.6 ng/L. The developed method was successfully applied on environmental water samples. The SPE extracts of spiked ultrapure water, drinking water, river and wastewater effluent were stored for 70 days, and the ILSs-corrected recoveries of 27 PPCPs were obtained to evaluate the correction ability of ILSs in the presence of variety interferences. The recoveries of 27 PPCPs over 70 days were within the scope of 72%–140% with the recovery variation<37% in all cases. The isotope dilution method seems to be of benefit when the extract has to be stored for long time before the instrument analysis.

关键词: Pharmaceuticals and personal care products (PPCPs)     Isotopically labeled standard (ILSs)     Water     Solid-phase extraction (SPE)     LC-MS/MS    

Efficient conversion of lignin to alkylphenols over highly stable inverse spinel MnFeO catalysts

《化学科学与工程前沿(英文)》 2023年 第17卷 第8期   页码 1085-1095 doi: 10.1007/s11705-022-2236-1

摘要: The aromatic properties of lignin make it a promising source of valuable chemicals and fuels. Developing efficient and stable catalysts to effectively convert lignin into high-value chemicals is challenging. In this work, MnFe2O4 spinel catalysts with oxygen-rich vacancies and porous distribution were synthesized by a simple solvothermal process and used to catalyze the depolymerization of lignin in an isopropanol solvent system. The specific surface area was 110.5 m2∙g–1, which substantially increased the active sites for lignin depolymerization compared to Fe3O4. The conversion of lignin reached 94%, and the selectivity of alkylphenols exceeded 90% after 5 h at 250 °C. Underpinned by characterizations, products, and density functional theory analysis, the results showed that the catalytic performance of MnFe2O4 was attributed to the composition of Mn and Fe with strong Mn–O–Fe synergy. In addition, the cycling experiments and characterization showed that the depolymerized lignin on MnFe2O4 has excellent cycling stability. Thus, our work provides valuable insights into the mechanism of lignin catalytic depolymerization and paves the way for the industrial-scale application of this process.

关键词: lignin depolymerization     spinel     catalysts     hydrogenation    

Planar jumping with stable landing through foot orientation design and ankle joint control

Qilong YUAN, I-Ming CHEN

《机械工程前沿(英文)》 2012年 第7卷 第2期   页码 100-108 doi: 10.1007/s11465-012-0318-3

摘要:

This paper introduces a method to generate the planar jumping motion for biped robot. In this work, through determining the upper body posture trajectory in the flight phase, the foot landing posture is made to be flat while landing. Together with properly designing the trajectory for local center of gravity and the foot landing velocity, the soft landing trajectory is generated. A controller on the ankle joint is added to avoid significant impact with the ground and stabilize the robot after landing. Jumping motion with stable landing is achieved in a dynamic simulation environment based on this method.

关键词: biped jumping     stable landing control     jumping motion generation    

环境同位素示踪方法研究新安江右坝肩绕坝渗流

陈建生,刘建刚,董海洲,陈亮

《中国工程科学》 2004年 第6卷 第1期   页码 57-63

摘要:

通过分析新安江右坝区环境水中的同位素2H,18O,3H以及温度与电导分布,研究新安江右坝存在的绕坝渗流场。环境同位素数据证实了右坝肩基岩中存在着绕坝渗漏,排水廊道中的排水既有边坡降雨入渗,又有库水的绕坝肩补给,排水廊道扇形孔中的渗水完全来自于绕坝肩的库水渗漏。3E1-1扬压力升高的原因是由于F0断层渗漏造成的结果,但6坝段和7坝段下部的F1断层基本上不存在渗漏,灌浆廊道G7-4排水孔中渗水中的3H高达19.54TU,证实该渗漏水来自坝后区的降雨补给。右坝肩观测孔R3和R6等孔中发现绕坝库水成分,环境同位素数据同时证实了人工示踪方法得到的结论。

关键词: 环境同位素     绕坝渗流     大气降水     水库    

Engineering the grain boundary: a promising strategy to configure NiCoPO/NiCoP nanowire arrays for ultra-stable

《化学科学与工程前沿(英文)》 2022年 第16卷 第8期   页码 1259-1267 doi: 10.1007/s11705-021-2132-0

摘要: NiCoP4O12/NiCoP nanorod-like arrays with tunable grain boundary density and pores were synthesized by the processes composed of hydrothermal and pyrolysis, in which, the electron structure of Ni and Co atoms characterized by X-ray photoelectron spectroscopy was contemporaneous inverse manipulated. The optimized NiCoP4O12/NiCoP arrays have a high specific capacitance of 507.8 μAh∙cm–2 at 1 mA∙cm–2, and good rate ability of 64.7% retention at 30-folds increased current density. Importantly, an ultra-stable ability, 88.5% of retention after 10000 cycles, was achieved in an asymmetric cell assembled of the NiCoP4O12/NiCoP arrays with activated carbon. In addition, the energy and power densities of an asymmetric cell were higher than those of other work, demonstrating as-prepared NiCoP4O12/NiCoP arrays are promising electrodes for supercapacitors.

关键词: NiCo     array electrode     grain boundary     stability     supercapacitor    

Optimising the oil phases of aluminium hydrogel-stabilised emulsions for stable, safe and efficient vaccine

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 973-984 doi: 10.1007/s11705-021-2123-1

摘要: To increase antibody secretion and dose sparing, squalene-in-water aluminium hydrogel (alum)-stabilised emulsions (ASEs) have been developed, which offer increased surface areas and cellular interactions for higher antigen loading and enhanced immune responses. Nevertheless, the squalene (oil) in previous attempts suffered from limited oxidation resistance, thus, safety and stability were compromised. From a clinical translational perspective, it is imperative to screen the optimal oils for enhanced emulsion adjuvants. Here, because of the varying oleic to linoleic acid ratio, soybean oil, peanut oil, and olive oil were utilised as oil phases in the preparation of aluminium hydrogel-stabilised squalene-in-water emulsions, which were then screened for their stability and immunogenicity. Additionally, the underlying mechanisms of oil phases and emulsion stability were unravelled, which showed that a higher oleic to linoleic acid ratio increased anti-oxidative capabilities but reduced the long-term storage stability owing to the relatively low zeta potential of the prepared droplets. As a result, compared with squalene-in-water ASEs, soybean-in-water ASEs exhibited comparable immune responses and enhanced stability. By optimising the oil phase of the emulsion adjuvants, this work may offer an alternative strategy for safe, stable, and effective emulsion adjuvants.

关键词: pickering emulsion     vaccine adjuvant     alum-stabilised emulsion     oleic to linoleic acid ratio     stability    

Effective and selective separation of perrhenate from acidic wastewater by super-stable, superhydrophobic

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1456-9

摘要:

• A ZnO-biochar hybrid composite was prepared by solvothermal-pyrolysis synthesis.

关键词: Selectivity     Adsorption     Re(VII)     ZnO     Biochar    

g-CN-coated MnO hollow nanorod cathode for stable aqueous Zn-ion batteries

《化学科学与工程前沿(英文)》 2023年 第17卷 第2期   页码 217-225 doi: 10.1007/s11705-022-2214-7

摘要: Aqueous zinc-ion batteries are attracting considerable attention because of their high safety compared with conventional lithium-ion batteries. Manganese-based materials have been widely developed for zinc-ion batteries cathode owning to their low cost, high security and simple preparation. However, the severe volume expansion and poor stability during charging and discharging limit the further development of manganese-based cathodes. Herein, superior α-MnO2@g-C3N4 was successfully prepared for stable zinc-ion batteries (ZIBs) cathode by introducing g-C3N4 nanosheets. Compared with pure α-MnO2, α-MnO2@g-C3N4 has a specific capacity of 298 mAh·g–1 at 0.1 A·g–1. Even at 1 A·g–1, the α-MnO2@g-C3N4 still retains 100 mAh·g–1 (83.4% retention after 5000 cycles), implying its excellent cycling stability. The α-MnO2@g-C3N4-based cathode has the highest energy density (563 Wh·kg–1) and power energy density (2170 W·kg–1). This work provides new avenues for the development of a wider range of cathode materials for ZIBs.

关键词: α-MnO2 hollow nanorods     g-C3N4     heterojunction     aqueous Zn-ion batteries    

Preparation and performance of novel thermal stable composite nanofiltration membrane

WU Chunrui, ZHANG Shouhai, YANG Fajie, YAN Chun, JIAN Xigao

《化学科学与工程前沿(英文)》 2008年 第2卷 第4期   页码 402-406 doi: 10.1007/s11705-008-0063-7

摘要: The novel thermal stable composite nanofiltration membranes were prepared through the interfacial polymerization of piperazine and trimesoyl chloride on the poly (phthalazinone ether) ultrafiltration substrate. The effects of polymerization and testing conditions on membrane performance were studied. The surface morphologies of the substrate and the composite membranes were observed by means of scanning electron microscopy (SEM) and atomic force microscopy (AFM). The separation properties of membranes for dyes and salts were tested. The composite membranes show good thermal stability. The rejection for NaSO was kept over 96%, while the flux reached 400 L·m·h when it was tested at 1.0 MPa and 80°C. When tested at 1.0 MPa and 60°C, the rejection of the composite membrane for dyes was kept at high level, and the flux reached 180–210 Lm·h, while the rejection for NaCl was lower than 20%.

关键词: electron microscopy     rejection     composite membrane     interfacial polymerization     thermal stability    

Conversion of CO into CO by high active and stable PdNi nanoparticles supported on a metal-organic framework

《化学科学与工程前沿(英文)》 2022年 第16卷 第7期   页码 1139-1148 doi: 10.1007/s11705-021-2111-5

摘要: The solubility of Pd(NO3)2 in water is moderate whereas it is completely soluble in diluted HNO3 solution. Pd/MIL-101(Cr) and Pd/MIL-101-NH2(Cr) were synthesized by aqueous solution of Pd(NO3)2 and Pd(NO3)2 solution in dilute HNO3 and used for CO oxidation reaction. The catalysts synthesized with Pd(NO3)2 solution in dilute HNO3 showed lower activity. The aqueous solution of Pd(NO3)2 was used for synthesis of mono-metal Ni, Pd and bimetallic PdNi nanoparticles with various molar ratios supported on MOF. Pd70Ni30/MIL-101(Cr) catalyst showed higher activity than monometallic counterparts and Pd+ Ni physical mixture due to the strong synergistic effect of PdNi nanoparticles, high distribution of PdNi nanoparticles, and lower dissociation and desorption barriers. Comparison of the catalysts synthesized by MIL-101(Cr) and MIL-101-NH2(Cr) as the supports of metals showed that Pd/MIL-101-NH2(Cr) outperforms Pd/MIL-101-(Cr) because of the higher electron density of Pd resulting from the electron donor ability of the NH2 functional group. However, the same activities were observed for Pd70Ni30/MIL-101(Cr) and Pd70Ni30/MIL-101-NH2(Cr), which is due to a less uniform distribution of Pd nanoparticles in Pd70Ni30/MIL-101-NH2(Cr) originated from amorphization of MIL-101-NH2(Cr) structure during the reduction process. In contrast, Pd70Ni30/MIL-101(Cr) revealed the stable structure and activity during reduction and CO oxidation for a long time.

关键词: CO oxidation     heterogeneous catalysis     metal-organic framework     NH2 functional group     PdNi    

Isolating higher yielding and more stable rice genotypes in stress environments: fine-tuning a selection

《农业科学与工程前沿(英文)》 doi: 10.15302/J-FASE-2023521

摘要:

● Score index methods readily discriminate genotypes adapted to a target environment.

关键词: Aerobic rice     breeding selection     drought resilience     production capacity index     resilience capacity index     stress score index     upland    

SUSTAINABLE NITROGEN MANAGEMENT IN AUSTRALIAN AGROECOSYSTEMS: CHALLENGES AND OPPORTUNITIES

《农业科学与工程前沿(英文)》 2022年 第9卷 第3期   页码 366-372 doi: 10.15302/J-FASE-2022447

摘要:

● There is huge potential for improvement of nitrogen management in Australia.

关键词: Australian agroecosystems     reactive nitrogen     sustainable development    

标题 作者 时间 类型 操作

δN-stable isotope analysis of NH: An overview on analytical measurements, source sampling and its source

期刊论文

Nitrogen pollution and source identification of urban ecosystem surface water in Beijing

Yufen REN, Zhiwei XU, Xinyu ZHANG, Xiaoke WANG, Xiaomin SUN, D. J. BALLANTINE, Shengzhong WANG

期刊论文

communities biostimulated by ethanol during uranium (VI) bioremediation in contaminated sediment as shown by stableisotope probing

Mary Beth LEIGH,Wei-Min WU,Erick CARDENAS,Ondrej UHLIK,Sue CARROLL,Terry GENTRY,Terence L. MARSH,Jizhong ZHOU,Philip JARDINE,Craig S. CRIDDLE,James M. TIEDJE

期刊论文

Determination of 27 pharmaceuticals and personal care products (PPCPs) in water: The benefit of isotope

Xueqi Fan, Jie Gao, Wenchao Li, Jun Huang, Gang Yu

期刊论文

Efficient conversion of lignin to alkylphenols over highly stable inverse spinel MnFeO catalysts

期刊论文

Planar jumping with stable landing through foot orientation design and ankle joint control

Qilong YUAN, I-Ming CHEN

期刊论文

环境同位素示踪方法研究新安江右坝肩绕坝渗流

陈建生,刘建刚,董海洲,陈亮

期刊论文

Engineering the grain boundary: a promising strategy to configure NiCoPO/NiCoP nanowire arrays for ultra-stable

期刊论文

Optimising the oil phases of aluminium hydrogel-stabilised emulsions for stable, safe and efficient vaccine

期刊论文

Effective and selective separation of perrhenate from acidic wastewater by super-stable, superhydrophobic

期刊论文

g-CN-coated MnO hollow nanorod cathode for stable aqueous Zn-ion batteries

期刊论文

Preparation and performance of novel thermal stable composite nanofiltration membrane

WU Chunrui, ZHANG Shouhai, YANG Fajie, YAN Chun, JIAN Xigao

期刊论文

Conversion of CO into CO by high active and stable PdNi nanoparticles supported on a metal-organic framework

期刊论文

Isolating higher yielding and more stable rice genotypes in stress environments: fine-tuning a selection

期刊论文

SUSTAINABLE NITROGEN MANAGEMENT IN AUSTRALIAN AGROECOSYSTEMS: CHALLENGES AND OPPORTUNITIES

期刊论文