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1. New insights into eutrophication management: Importance of temperature and water residence time

Author:
Zhao, Feng; Zhan, Xu; Xu, Hai; Zhu, Guangwei; Zou, Wei; Zhu, Mengyuan; Kang, Lijuan; Guo, Yulong; Zhao, Xingchen; Wang, Zicong; Tang, Wei
Source:
Journal of environmental sciences (China) 2022 v.111 pp. 229-239
ISSN:
1001-0742
Subject:
nitrogen; nitrogen fixation; nitrogen-fixing cyanobacteria,   etc   ; Cyanobacteria; climate; eutrophication; freshwater; humans; phosphorus; spectrometers; water quality; water temperature; China;     Show all 13 Subjects
Abstract:
... Eutrophication and harmful cyanobacterial blooms threaten water resources all over the world. There is a great controversy about controlling only phosphorus or controlling both nitrogen and phosphorus in the management of lake eutrophication. The primary argument against the dual nutrients control of eutrophication is that nitrogen fixation can compensate the nitrogen deficits. Thus, it is of grea ...
DOI:
10.1016/j.jes.2021.02.033

2. Varying water column stability controls the denitrification process in a subtropical reservoir, Southwest China

Author:
Cui, Gaoyang; Li, Xiao-Dong; Li, Siqi; Ding, Shiyuan; Li, Qinkai; Yang, Mengdi; Lv, Hong; Wang, Yiyao
Source:
Journal of environmental sciences (China) 2022 v.111 pp. 208-219
ISSN:
1001-0742
Subject:
nitrogen,   etc   ; denitrification; eutrophication; hydrology; nitrates; nitrification; nitrous oxide; oxygen; summer; temperature profiles; winter; China;     Show all 12 Subjects
Abstract:
... Reservoirs are regarded as hotspots of nitrogen transformation and potential sources of nitrous oxide (N₂O). However, it remains unclear how the hydrological conditions due to dam construction control the processes of nitrogen transformation in reservoir waters. To address this issue, we examined the spatial-temporal characteristics of nitrate concentrations, δ¹⁵N-NO₃⁻, δ¹⁸O-NO₃⁻, δ¹⁸O-H₂O, relati ...
DOI:
10.1016/j.jes.2021.02.034

3. Atmospheric nitrogen deposition: A review of quantification methods and its spatial pattern derived from the global monitoring networks

Author:
Zhang, Qi; Li, Yanan; Wang, Mengru; Wang, Kai; Meng, Fanlei; Liu, Lei; Zhao, Yuanhong; Ma, Lin; Zhu, Qichao; Xu, Wen; Zhang, Fusuo
Source:
Ecotoxicology and environmental safety 2021 v.216 pp. 112180
ISSN:
0147-6513
Subject:
nitrogen; nitrogen cycle; total nitrogen,   etc   ; ecotoxicology; satellites; China;     Show all 6 Subjects
Abstract:
... Atmospheric nitrogen (N) deposition is a vital component of the global N cycle. Excessive N deposition on the Earth’s surface has adverse impacts on ecosystems and humans. Quantification of atmospheric N deposition is indispensable for assessing and addressing N deposition-induced environmental issues. In the present review, we firstly summarized the current methods applied to quantify N depositio ...
DOI:
10.1016/j.ecoenv.2021.112180

4. Conversion of nitrogen and carbon in enriched paddy soil by denitrification coupled with anammox in a bioelectrochemical system

Author:
Zhang, Luan; Jiang, Minghe; Zhou, Shungui
Source:
Journal of environmental sciences (China) 2022 v.111 pp. 197-207
ISSN:
1001-0742
Subject:
nitrogen,   etc   ; Dechloromonas; ammonium; anaerobic ammonium oxidation; anodes; bioelectrochemistry; carbon; cathodes; denitrification; dominant species; microbial communities; paddy soils; China;     Show all 13 Subjects
Abstract:
... The aim of this study is to investigate conversion of nitrogen and COD in enriched paddy soil by nitrification coupled with anammox process in a dual chamber bioelectrochemical system. The paddy soil was enriched for denitrification coupled with anammox by microbial consortia and was acclimatized in the cathodic chamber of microbial fuel cells (MFCs). The bioelectrochemical systems were treated wi ...
DOI:
10.1016/j.jes.2021.03.033

5. Analysis of the Correlation between the Phytoplankton Development Level, Assessed by Chlorophyll a, and Nutrient Concentrations in Rybinsk Reservoir

Author:
Stepanova, I. E.
Source:
Biology bulletin of the Russian Academy of Sciences 2021 v.48 no.2 pp. 193-198
ISSN:
1062-3590
Subject:
nitrogen; total nitrogen,   etc   ; chlorophyll; phosphorus; phytoplankton;     Show all 5 Subjects
Abstract:
... A correlation analysis between chlorophyll a, nitrogen, and phosphorus compounds in Rybinsk Reservoir is carried out. During certain periods of the study, a significant correlation between chlorophyll a and inorganic nitrogen and phosphorus compounds is shown. The response of phytoplankton to the total nitrogen and phosphorus concentrations is evaluated. ...
DOI:
10.1134/S1062359021020114

6. Nitrogen and the food system

Author:
Metson, Geneviève S.; Chaudhary, Abhishek; Zhang, Xin; Houlton, Benjamin; Oita, Azusa; Raghuram, Nandula; Read, Quentin D.; Bouwman, Lex; Tian, Hanqin; Uwizeye, Aimable; Eagle, Alison J.
Source:
One earth 2021 v.4 no.1 pp. 3-7
ISSN:
2590-3322
Subject:
nitrogen; nitrogen cycle,   etc   ; food security; hunger; pollutants;     Show all 5 Subjects
Abstract:
... To stave off world hunger, humanity manipulated and unbalanced the nitrogen cycle. Today’s excess fixed nitrogen is a global pollutant, of which our food system is a primary driver. Yet, food insecurity remains a global concern. In this Voices, food-system experts offer insights into the challenge of the sustainable management of nitrogen. ...
DOI:
10.1016/j.oneear.2020.12.018

7. Dipnictogen f-Element Chemistry: A Diphosphorus Uranium Complex

Author:
Du, Jingzhen; Hunger, David; Seed, John A.; Cryer, Jonathan D.; King, David M.; Wooles, Ashley J.; van Slageren, Joris; Liddle, Stephen T.
Source:
Journal of the American Chemical Society 2021 v.143 no.14 pp. 5343-5348
ISSN:
1520-5126
Subject:
nitrogen,   etc   ; chemistry; ligands; uranium;     Show all 4 Subjects
Abstract:
... The first isolation and structural characterization of an f-element dinitrogen complex was reported in 1988, but an f-element complex with the first heavier group 15 homologue diphosphorus has to date remained unknown. Here, we report the synthesis of a side-on bound diphosphorus complex of uranium(IV) using a 7λ³-(dimethylamino)phosphadibenzonorbornadiene-mediated P atom transfer approach. Experi ...
DOI:
10.1021/jacs.1c02482

8. Copper–CNT interfacing with Cu-doped polydopamine in CNT carpet: copper nucleation and resistance decrease upon soft annealing

Author:
Duhain, Antoine; Guillot, Jérôme; Lamblin, Guillaume; Lenoble, Damien
Source:
RSC advances 2021 v.11 no.20 pp. 11900-11909
ISSN:
2046-2069
Subject:
nitrogen,   etc   ; copper; temperature;     Show all 3 Subjects
Abstract:
... In recent years, Cu–CNT composites have attracted much attention due to their remarkable properties, in comparison to pure copper, such as higher ampacity and a lower thermal coefficient of resistance. However, the fabrication of an efficient Cu–CNT composite is still challenging, mainly due to the high cuprophobicity of CNTs. To strengthen the chemical interactions between Cu and CNTs, we propose ...
DOI:
10.1039/d0ra09369f

9. Synthesis of an azadioxa-planar triphenylborane and investigation of its structural and photophysical properties

Author:
Kitamoto, Y.; Oda, K.; Ogino, K.; Hiyama, K.; Kita, H.; Hattori, T.; Oi, S.
Source:
Chemical communications 2021 v.57 no.18 pp. 2297-2300
ISSN:
1364-548X
Subject:
nitrogen,   etc   ; Lewis bases; oxygen;     Show all 3 Subjects
Abstract:
... We report here the first successful synthesis of planar triphenylborane 1 with the phenyl groups bridged by oxygen and nitrogen atoms via double nucleophilic aromatic substitution reaction. The hetero atom-bridged 1 has excellent planarity. Its structural and photophysical properties are tunable by altering the bridging atoms. ...
DOI:
10.1039/d0cc08331c

10. Recent advances and prospects in the Zn-catalysed Mannich reaction

Author:
Shamna, Salahudeen; Afsina, C. M. A.; Philip, Rose Mary; Anilkumar, Gopinathan
Source:
RSC advances 2021 v.11 no.16 pp. 9098-9111
ISSN:
2046-2069
Subject:
nitrogen,   etc   ; catalysts; ligands; toxicity;     Show all 4 Subjects
Abstract:
... Zn-catalysed reactions are ubiquitously important due to their inexpensive, generally less toxic and atom-economic nature. According to the modern criteria of sustainability, their use in a catalytic manner is a highly desirable goal, especially when using chiral ligands. Considering the relevance of well-established zinc-mediated C–C bond formation reactions, it is relatively surprising that the ...
DOI:
10.1039/d0ra10772g

11. The urban nitrogen challenge

Author:
Seddon, Jessica; Smit, Warren; Kheirbek, Iyad; Gu, Baojing
Source:
One earth 2021 v.4 no.1 pp. 8-9
ISSN:
2590-3322
Subject:
nitrogen,   etc   ; human health; pollution;     Show all 3 Subjects
Abstract:
... Cities are our future, yet our activities have transformed cities into new hotspots of nitrogen deposition, leading to detrimental consequences for human health. In the wake of 2019’s Colombo Declaration, this Voices asks, how can we manage nitrogen pollution sustainably to provide a clean urban future for all? ...
DOI:
10.1016/j.oneear.2020.12.019

12. Modulation of destructive quantum interference by bridge groups in truxene-based single-molecule junctions

Author:
Wang, Lin; Zhao, Zhihao; Shinde, Digambar B.; Lai, Zhiping; Wang, Dong
Source:
Chemical communications 2021 v.57 no.5 pp. 667-670
ISSN:
1364-548X
Subject:
nitrogen,   etc   ; electron transfer; energy;     Show all 3 Subjects
Abstract:
... Electron transport properties of polycyclic truxene derivatives have been investigated by the single molecule conductance measurement technique and theoretical study. Molecules with nitrogen and carbonyl substituents at the bridge sites exhibit higher single-molecule conductances by almost one order of magnitude compared with non-substituted analogues. It can be ascribed that the anti-resonance fe ...
DOI:
10.1039/d0cc07438a

13. A novel of spacecraft flexible compartment safe and stable inflatable expansion system with the environmental-friendly fuel

Author:
Han, Zhiyue; Gong, Li; Yan, Suxin; Cao, Wei; Hng, Huey Hoon; Du, Zhiming; Yu, Yue
Source:
Journal of cleaner production 2021 v.279 pp. 123843
ISSN:
0959-6526
Subject:
nitrogen,   etc   ; combustion; spacecraft; temperature;     Show all 4 Subjects
Abstract:
... At present, the inflatable expansion of a flexible compartment of a spacecraft mainly depends on the compressed gas cylinder. However, there are some problems in the technology of compressed gas cylinders, such as large volume, heavy mass and non-environmental protection. In view of the above problems, a new space inflatable deployment system is innovatively proposed in this work. The system mainl ...
DOI:
10.1016/j.jclepro.2020.123843

14. Comparative DFT study of the effectiveness of p-phenylenediamine antioxidants through their coordination ability towards the late 1st row transition metals

Author:
Jelemenská, Ingrid; Breza, Martin
Source:
Polymer degradation and stability 2021 v.183 pp. 109438
ISSN:
0141-3910
Subject:
nitrogen,   etc   ; antioxidants; degradation; polymers;     Show all 4 Subjects
Abstract:
... Interaction energies, metal atom charges and electron density Laplacians at bond critical points of metal – nitrogen bonds in [Aox…M]²⁺ complexes of a series of p-phenylenediamine antioxidants (Aox) with the late 1ˢᵗ row transition metals M(II) in various spin states were evaluated in order to predict the antioxidant effectiveness through their coordination ability. The complexes without exclusive ...
DOI:
10.1016/j.polymdegradstab.2020.109438

15. Research progress and hotspot analysis for reactive nitrogen flows in macroscopic systems based on a CiteSpace analysis

Author:
Zhang, Xiaolin; Zhang, Yan; Wang, Yifan; Fath, Brian D.
Source:
Ecological modelling 2021 v.443 pp. 109456
ISSN:
0304-3800
Subject:
nitrogen; nitrogen cycle,   etc   ; cluster analysis; computer software; evolution; humans; urbanization;     Show all 7 Subjects
Abstract:
... Human activities have significantly changed the global nitrogen cycle and its underlying processes. Many scholars have studied flows of reactive nitrogen at a range of spatial and temporal scales. However, due to the complexity of the research subject, the diversified research content and methods, and the wide range of research scales, there has been no systematic synthesis of the research in this ...
DOI:
10.1016/j.ecolmodel.2021.109456

16. Enriched oxygen vacancies of Cu2O/SnS2/SnO2 heterostructure for enhanced photocatalytic reduction of CO2 by water and nitrogen fixation

Author:
Ojha, Niwesh; Bajpai, Abhinav; Kumar, Sushant
Source:
Journal of colloid and interface science 2021 v.585 pp. 764-777
ISSN:
0021-9797
Subject:
nitrogen; nitrogen fixation,   etc   ; carbon dioxide; lighting; nanocomposites; oxygen; photocatalysis;     Show all 7 Subjects
Abstract:
... When two semiconductors are electronically coupled, their photocatalytic performance can be greatly enhanced. Herein, we formed a heterostructure between Cu₂O and SnS₂/SnO₂ nanocomposite using a solvothermal reactor, which reduced CO₂ by H₂O at ambient conditions to produce CO, H₂, and CH₄. With inclusion of Cu₂O, apparent quantum yield, a measure of photoactivity, has increased from 7.16% to 8.62 ...
DOI:
10.1016/j.jcis.2020.10.056

17. Fed-batch culture of Oplopanax elatus adventitious roots: Feeding medium selection through comprehensive evaluation using an analytic hierarchy process

Author:
Jiang, X.L.; Jin, M.Y.; Piao, X.C.; Yin, C.R.; Lian, M.L.
Source:
Biochemical engineering journal 2021 v.167 pp. 107927
ISSN:
1369-703X
Subject:
nitrogen; nitrogen content,   etc   ; Oplopanax; adventitious roots; flavonoids; phosphorus; polysaccharides; sucrose;     Show all 8 Subjects
Abstract:
... Adventitious root (AR) culture is an efficient route for the production of bioactive compounds of Oplopanax elatus. In fed-batch culture, selecting feeding media is a critical strategy for the successful culture. Therefore, this study examined the effects of four feeding medium factors (sucrose concentration, medium salt strength, phosphorus and nitrogen concentration) on culture efficiency of O. ...
DOI:
10.1016/j.bej.2021.107927

18. In situ modification of cobalt on MXene/TiO2 as composite photocatalyst for efficient nitrogen fixation

Author:
Gao, Wanguo; Li, Xiaoman; Luo, Shijian; Luo, Zhenglong; Zhang, Xu; Huang, Rong; Luo, Min
Source:
Journal of colloid and interface science 2021 v.585 pp. 20-29
ISSN:
0021-9797
Subject:
nitrogen; nitrogen fixation,   etc   ; active sites; cobalt; desorption; nanosheets; photocatalysis; photocatalysts;     Show all 8 Subjects
Abstract:
... Modulation of the binding of the reactant or product species with catalysts is an effective approach to optimize the photocatalytic activity. Herein, we explored the relationship between the binding of reactant (N₂) and product (NH₃) with catalyst and the photocatalytic nitrogen fixation activity. The surface reactivity of nitrogen with water was tuned by introducing Co into the MXene@TiO₂ catalys ...
DOI:
10.1016/j.jcis.2020.11.064

19. Entropy differences between hydrides and other elements

Author:
Kojima, Yoshitsugu; Yamaguchi, Masakuni
Source:
Chemical communications 2021 v.57 no.28 pp. 3461-3463
ISSN:
1364-548X
Subject:
liquid nitrogen,   etc   ; entropy; equations; toluene;     Show all 4 Subjects
Abstract:
... The standard entropy differences between hydrides and other elements (metals, liquid N₂, toluene) ΔS were increased with the volume differences ΔV. It was found that ΔS is roughly expressed by the following equation, |ΔS| ∝ Rln|ΔV|, in which R is the gas constant. ...
DOI:
10.1039/d0cc07107b

20. Optimizing the use of open chambers to measure ammonia volatilization in field plots amended with urea

Author:
MARTINS, Márcio R.; SARKIS, Leonardo F.; SANT'ANNA, Selenobaldo A.C.; SANTOS, Camila A.; ARAUJO, Karla E.; SANTOS, Ricardo C.; ARAÚJO, Ednaldo S.; ALVES, Bruno J.R.; JANTALIA, Claudia P.; BODDEY, Robert M.; ZAMAN, Mohammad; URQUIAGA, Segundo
Source:
Pedosphere 2021 v.31 no.2 pp. 243-254
ISSN:
1002-0160
Subject:
nitrogen,   etc   ; ammonia; uncertainty; urea; volatilization;     Show all 5 Subjects
Abstract:
... Measuring ammonia (NH₃) volatilization from urea-fertilized soils is crucial for evaluation of practices that reduce gaseous nitrogen (N) losses in agriculture. The small area of chambers used for NH₃ volatilization measurements compared with the size of field plots may cause significant errors if inadequate sampling strategies are adopted. Our aims were: i) to investigate the effect of using mult ...
DOI:
10.1016/S1002-0160(20)60078-9