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1. 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 content,   etc   ; Oplopanax; adventitious roots; flavonoids; nitrogen; 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

2. Soil Nitrogen Dynamics in a Managed Temperate Grassland Under Changed Climatic Conditions

Author:
Giraud, Mona; Groh, Jannis; Gerke, Horst H.; Brüggemann, Nicolas; Vereecken, Harry; Pütz, Thomas
Source:
Water 2021 v.13 no.7
ISSN:
2073-4441
Subject:
nitrogen content; plant nitrogen content,   etc   ; annuals; ecosystems; fertilizers; grasslands; groundwater; lysimeters; mineralization; nitrates; nitrogen; nitrogen balance; soil; soil solution; water stress;     Show all 15 Subjects
Abstract:
... Grasslands are one of the most common biomes in the world with a wide range of ecosystem services. Nevertheless, quantitative data on the change in nitrogen dynamics in extensively managed temperate grasslands caused by a shift from energy- to water-limited climatic conditions have not yet been reported. In this study, we experimentally studied this shift by translocating undisturbed soil monolith ...
DOI:
10.3390/w13070931

3. Predicting leaf nitrogen content in olive trees using hyperspectral data for precision agriculture

Author:
Rubio-Delgado, Judit; Pérez, Carlos J.; Vega-Rodríguez, Miguel A.
Source:
Precision agriculture 2021 v.22 no.1 pp. 1-21
ISSN:
1385-2256
Subject:
leaf nitrogen content; nitrogen content,   etc   ; absorption; calibration; chlorophyll; leaves; nitrogen; olives; orchards; precision agriculture; prediction; reflectance; uncertainty; vegetation; Mediterranean region; Spain;     Show all 16 Subjects
Abstract:
... Olive orchard is one of the main crops in the Mediterranean basin and, particularly, in Spain, with 56% of European production. In semi-arid regions, nitrogen (N) is the main limiting factor of olive trees after water and its quantification is essential to carry out accurate fertilization planning. In the present study, N status of an olive orchard located in Carmonita (southwest Spain) was analys ...
DOI:
10.1007/s11119-020-09727-1

4. Sensitivity of soil nitrifying and denitrifying microorganisms to nitrogen deposition on the Qinghai–Tibetan plateau

Author:
Xu, Minjie; Li, Tingting; Liu, Wei; Ding, Junjun; Gao, Lili; Han, Xingguo; Zhang, Ximei
Source:
Annals of microbiology 2021 v.71 no.1 pp. 6
ISSN:
1590-4261
Subject:
nitrogen content,   etc   ; atmospheric deposition; denitrification; denitrifying microorganisms; ecosystems; genes; methodology; nitrogen; soil; toxicity; China;     Show all 11 Subjects
Abstract:
... PURPOSE: Nitrogen deposition at rate not more than 50 kg ha⁻¹ year⁻¹ is generally considered to stimulate soil nitrifying and denitrifying microorganisms via increases in soil nitrogen content. However, this phenomenon in alpine ecosystems remains largely untested. METHODS: We conducted an 8-year nitrogen deposition experiment on the Qinghai–Tibetan Plateau, with four nitrogen deposition rates of ...
DOI:
10.1186/s13213-020-01619-z

5. Nature inspired approach to mimic design for increased specific capacitance as supercapacitor electrodes

Author:
Lee, Kwang Se; Phiri, Isheunesu; Park, Chan Woo; Kim, Saeheon; Ko, Jang Myoun
Source:
Journal of colloid and interface science 2021 v.592 pp. 42-50
ISSN:
0021-9797
Subject:
nitrogen content,   etc   ; Citrus; Escherichia coli; activated carbon; capacitance; electrochemical capacitors; electrochemistry; fruits; lemons; nitrogen;     Show all 10 Subjects
Abstract:
... In this study, the experiment was conducted assuming that the citrus fruits were contaminated with bacteria. Herein, orange peels (OP) and lemon peels (LP) can be used as a carbon source and have the advantage of using discarded materials and heteroatoms. Also, the nitrogen heteroatom is introduced by naturally doping the materials with bacteria (Escherichia Coli, E. coli). The as-prepared bacteri ...
DOI:
10.1016/j.jcis.2021.02.039

6. Spatial distribution of carbon, nitrogen and sulfur in surface soil across the Pearl River Delta area, South China

Author:
Zhang, Huihua; Kariman, Khalil; Zhu, Li; Liu, Yong; Chen, Junjian; Zhu, Li'an; Li, Dingqiang
Source:
Geoderma regional 2021 v.25 pp. e00390
ISSN:
2352-0094
Subject:
nitrogen content,   etc   ; agricultural land; carbon nitrogen ratio; nitrogen; organic carbon; river deltas; rivers; soil; sulfur; China;     Show all 10 Subjects
Abstract:
... In the present study, 885 surface soil samples were collected to study the spatial variations and correlations between total contents of organic carbon (C), nitrogen (N) and sulfur (S) in surface soil across the Pearl River Delta (PRD) area. The results showed that soil C and N had similar spatial patterns, and the soil C:N ratio had a relative stable value of 9.63, suggesting that soil biological ...
DOI:
10.1016/j.geodrs.2021.e00390

7. Application of real treated wastewater to starch production by microalgae: Potential effect of nutrients and microbial contamination

Author:
Noguchi, Mana; Aizawa, Ryo; Nakazawa, Daisuke; Hakumura, Yoshiki; Furuhashi, Yasuhiro; Yang, Sen; Ninomiya, Kazuaki; Takahashi, Kenji; Honda, Ryo
Source:
Biochemical engineering journal 2021 v.169 pp. 107973
ISSN:
1369-703X
Subject:
nitrogen content,   etc   ; activated sludge; biomass; carbohydrate content; chlorination; culture media; disinfection; microalgae; microbial contamination; starch; wastewater;     Show all 11 Subjects
Abstract:
... Some starch-accumulating microalgae are promising biomass resources for producing platform chemicals for biorefinery applications. The use of treated wastewater as the cultivation medium has been considered because real treated wastewater contains not only nutrients, but also bacteria from activated sludge. In this study, the potential feasibility of real treated wastewater for starch production b ...
DOI:
10.1016/j.bej.2021.107973

8. Efficient nitrogen doped porous carbonaceous CO2 adsorbents based on lotus leaf

Author:
Li, Qian; Liu, Shenfang; Wang, Linlin; Chen, Fangyuan; Shao, Jiawei; Hu, Xin
Source:
Journal of environmental sciences (China) 2021 v.103 pp. 268-278
ISSN:
1001-0742
Subject:
nitrogen content,   etc   ; adsorbents; adsorption; biomass; carbon dioxide; carbonization; heat; leaves; melamine; nitrogen; porous media; China;     Show all 12 Subjects
Abstract:
... In this work, the waste biomass lotus leaf was converted into N-doped porous carbonaceous CO₂ adsorbents. The synthesis process includes carbonization of lotus leaf, melamine post-treatment and KOH activation. For the resultant sorbents, high nitrogen content can be contained due to the melamine modification and advanced porous structure were formed by KOH etching. These samples were carefully cha ...
DOI:
10.1016/j.jes.2020.11.008

9. Mechanisms of persulfate activation on biochar derived from two different sludges: Dominance of their intrinsic compositions

Author:
Wu, Wei; Zhu, Shishu; Huang, Xiaochen; Wei, Wei; Ni, Bing-Jie
Source:
Journal of hazardous materials 2021 v.408 pp. 124454
ISSN:
0304-3894
Subject:
nitrogen content,   etc   ; biochar; carbon; phenol; polymerization; reactive oxygen species; remediation; sludge;     Show all 8 Subjects
Abstract:
... Sludge-derived biochar (SDBC) has been regarded as persulfate (PS) activator during the remediation of organic contamination. However, the complexity of sludge composition makes it difficult to predict the activity of SDBC and the efficacy of PS. To improve the understanding of how the composition of sludge regulated activity of its parent SDBC towards PS activation, we used two SDBCs derived from ...
DOI:
10.1016/j.jhazmat.2020.124454

10. The role of auxin in nitrogen-modulated shoot branching

Author:
Hou, Mengmeng; Wu, Daxia; Li, Ying; Tao, Wenqing; Chao, Ling; Zhang, Yali
Source:
Plant signaling & behavior 2021 v.16 no.4 pp. 1885888
ISSN:
1559-2324
Subject:
plant nitrogen content,   etc   ; ammonium; auxins; behavior; crop production; exports; nitrates; plant development; soil;     Show all 9 Subjects
Abstract:
... Shoot branching is determined by axillary bud formation and outgrowth and remains one of the most variable determinants of yield in many crops. Plant nitrogen (N) acquired mainly in the forms of nitrate and ammonium from soil, dominates plant development, and high-yield crop production relies heavily on N fertilization. In this review, the regulation of axillary bud outgrowth by N availability and ...
DOI:
10.1080/15592324.2021.1885888

11. Nitrogen content of the exuviae of Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae)

Author:
Tong, Reina L.; Aguilera-Olivares, Daniel; Chouvenc, Thomas; Su, Nan-Yao
Source:
Heliyon 2021 v.7 no.4 pp. e06697
ISSN:
2405-8440
Subject:
nitrogen content,   etc   ; Blattodea; Coptotermes gestroi; carbon; ecdysis; integument; nitrogen; subterranean termites; wood;     Show all 9 Subjects
Abstract:
... Subterranean termites are hemimetabolous social insects where most of the individuals in a colony molt on a regular basis until they die. Nitrogen is a limiting growth factor in wood-feeding insects, such as termites. Because the exuviae of molting termites are consumed by nestmates, it is possible that exuviae represent a potential source of nitrogen that could be recycled and be part of the over ...
DOI:
10.1016/j.heliyon.2021.e06697

12. N-rich porous organic polymers based on Schiff base reaction for CO2 capture and mercury(II) adsorption

Author:
Sang, Yafei; Cao, Yiwen; Wang, Lizhi; Yan, Wei; Chen, Tianwen; Huang, Jianhan; Liu, You-Nian
Source:
Journal of colloid and interface science 2021 v.587 pp. 121-130
ISSN:
0021-9797
Subject:
nitrogen content,   etc   ; adsorbents; adsorption; carbon; carbon dioxide; melamine; mercury; nitrogen; polymerization; polymers; schiff bases; surface area;     Show all 12 Subjects
Abstract:
... Due to the p-π conjugative effect between the nitrogen atom of the amide and the carbonyl, the amide carbonyl has much low reactivity and the Schiff base reaction between the amide and amine usually did not take place, but after the amide was polymerized, it's quite different. Herein, benzene-1,3,5-triyltris((9H-carbazol-9-yl) methanone) (HTCZ) is not able to have the Schiff base reaction with mel ...
DOI:
10.1016/j.jcis.2020.12.002

13. Temperature affects carbon and nitrogen stable isotopic signatures of aquatic plants

Author:
Zhang, Peiyu; Kong, Xianghong; Bakker, Elisabeth S.; Xu, Jun; Zhang, Min
Source:
Aquatic sciences 2021 v.83 no.2 pp. 39
ISSN:
1015-1621
Subject:
nitrogen content,   etc   ; Elodea nuttallii; Potamogeton lucens; Vallisneria spiralis; carbon; macrophytes; nitrogen; photosynthesis; plant growth; temperature;     Show all 10 Subjects
Abstract:
... Aquatic plants are vital components of shallow aquatic ecosystems, and they can substantially contribute to food webs. However, the large spatial and temporal variations of δ¹³C and δ¹⁵N signatures of aquatic plants have hindered the interpretation of their trophic interactions with organisms at higher trophic levels, and the effects of temperature on plant isotopic signatures remain to be fully e ...
DOI:
10.1007/s00027-021-00794-8

14. Estimating canopy nitrogen concentration of sugarcane crop using in situ spectroscopy

Author:
Reyes-Trujillo, Aldemar; Daza-Torres, Martha C.; Galindez-Jamioy, Carlos A.; Rosero-García, Esteban E.; Muñoz-Arboleda, Fernando; Solarte-Rodriguez, Efrain
Source:
Heliyon 2021 v.7 no.3 pp. e06566
ISSN:
2405-8440
Subject:
nitrogen content,   etc   ; canopy; developmental stages; experimental design; leaf reflectance; nitrogen; reflectance spectroscopy; spectral analysis; sugarcane; vegetation;     Show all 10 Subjects
Abstract:
... Estimating nitrogen (N) concentration in situ is fundamental for managing the fertilization of the sugarcane crop. The purpose of this work was to develop estimation models that explain how N varies over time as a function of three spectral data transformations in two stages (plant cane and first ratoon) under variable rates of N application. A randomized complete-block experimental design was app ...
DOI:
10.1016/j.heliyon.2021.e06566

15. Natural β-Carotene Production by Blakeslea trispora Cultivated in Spanish-Style Green Olive Processing Wastewaters

Author:
Papadaki, Eugenia; Mantzouridou, Fani Th
Source:
Foods 2021 v.10 no.2
ISSN:
2304-8158
Subject:
nitrogen content,   etc   ; Blakeslea trispora; carotenoids; degradation; fungi; olives; phytotoxicity; research; sugars; synthesis; volume; wastewater;     Show all 12 Subjects
Abstract:
... In the current research, the potential of Spanish-style green olive processing wastewaters (lye and washing waters) exploitation toward natural β-carotene production by Blakeslea trispora was tested for the first time. Mating culture generated by the joint cultivation of the heterothallic fungal strains ATCC 14271 and 14272 in the non-sterile lye and washing waters was able to grow, achieving the ...
DOI:
10.3390/foods10020327

16. Bio-membrane based integrated systems for nitrogen recovery in wastewater treatment: Current applications and future perspectives

Author:
Ye, Yuanyao; Ngo, Huu Hao; Guo, Wenshan; Chang, Soon Woong; Nguyen, Dinh Duc; Varjani, Sunita; Ding, An; Bui, Xuan-Thanh; Nguyen, Dan Phuoc
Source:
Chemosphere 2021 v.265 pp. 129076
ISSN:
0045-6535
Subject:
nitrogen content,   etc   ; cell membranes; eutrophication; human population; membrane bioreactors; nitrogen; photobioreactors; wastewater; wastewater treatment;     Show all 9 Subjects
Abstract:
... Nitrogen removal is crucial in wastewater treatment process as excessive nitrogen content could result in eutrophication and degradation of aquatic ecosystems. Moreover, to satisfy the fast-growing need of fertilizers due to an increase in human population, recovering nitrogen from wastewater is of the most sustainable approach. Currently, the membrane technique integrated with biological processe ...
DOI:
10.1016/j.chemosphere.2020.129076

17. Optimization of the nitrogen and oxygen element distribution in microalgae by ammonia torrefaction pretreatment and subsequent fast pyrolysis process for the production of N-containing chemicals

Author:
Li, Cong; Zhu, Liang; Ma, Zhongqing; Yang, Youyou; Cai, Wei; Ye, Jiewang; Qian, Jun; Liu, Xiaohuan; Zuo, Zhaojiang
Source:
Bioresource technology 2021 v.321 pp. 124461
ISSN:
0960-8524
Subject:
nitrogen content,   etc   ; ammonia; feedstocks; indoles; microalgae; nitrogen; oxygen; pyridines; pyrolysis; pyrroles; temperature; torrefaction;     Show all 12 Subjects
Abstract:
... In this work, ammonia (NH₃) torrefaction pretreatment (ATP) was developed to optimize the nitrogen and oxygen element distribution of microalgae via the N-doping and oxygen removal reaction, which could obviously improve the potential use of microalgae as a feedstock for the production of N-heterocyclic chemicals through fast pyrolysis technology. The nitrogen content increased from 8.3% of raw mi ...
DOI:
10.1016/j.biortech.2020.124461

18. Assessing mining impacts: The influence of background geochemical conditions on diatom and macroinvertebrate communities in subarctic streams

Author:
Mykrä, Heikki; Kuoppala, Minna; Nykänen, Vesa; Tolonen, Katri; Turunen, Jarno; Vilmi, Annika; Karjalainen, Satu Maaria
Source:
Journal of environmental management 2021 v.278 pp. 111532
ISSN:
0301-4797
Subject:
nitrogen content,   etc   ; Bacillariophyceae; community structure; environmental management; geochemistry; gold; hydrochemistry; macroinvertebrates; phosphates; streams; Lapland; Scandinavia;     Show all 12 Subjects
Abstract:
... Mining has changed landscapes locally in northern Fennoscandia and there is an increasing pressure for exploitation of the remaining mineral deposits of the region. Mineral deposits, even if unmined, can strongly influence stream water chemistry, stream biological communities and the ability of organisms to tolerate stressors. Using data sampled from six mining areas with three active (gold and ch ...
DOI:
10.1016/j.jenvman.2020.111532

19. Scanty graphene-driven phase control and heteroatom functionalization of ZIF-67-derived CoP-draped N-doped carbon/graphene as a hybrid electrode for high-performance asymmetric supercapacitor

Author:
Gayathri, Sampath; Arunkumar, Paulraj; Han, Jong Hun
Source:
Journal of colloid and interface science 2021 v.582 pp. 1136-1148
ISSN:
0021-9797
Subject:
nitrogen content,   etc   ; active sites; capacitance; carbonization; cobalt; electrochemical capacitors; electrochemistry; electrodes; energy; energy density; graphene;     Show all 11 Subjects
Abstract:
... Zeolitic imidazolate framework (ZIF)-derived materials have been explored as promising electrode for energy storage, owing to their tunable composition, high porous structure, and heteroatom-based active sites. Herein, we report cobalt phosphide-draped N-doped carbon/graphene hybrid (CoP-NPC/GS) synthesized from ZIF-67 precursor via a single-step in-situ carbonization and phosphidation. The CoP-NP ...
DOI:
10.1016/j.jcis.2020.08.096

20. Experimental Research on the Conversion of Fuel Nitrogen in the Postcombustion Chamber of the Circulating Fluidized Bed

Author:
Xiao, Yuan; Song, Guoliang; Song, Weijian; Yang, Xueting; Lyu, Qinggang
Source:
Energy & fuels 2021 v.35 no.3 pp. 2416-2424
ISSN:
1520-5029
Subject:
nitrogen content,   etc   ; carbon; coal; combustion; energy; flue gas; fluidized beds; fly ash; furnaces; nitrogen;     Show all 10 Subjects
Abstract:
... The postcombustion technology involved the application of the deep air-staged combustion technology to circulating fluidized bed (CFB) combustion. To further develop its de-NOₓ potential, three kinds of fuel were adopted to investigate the conversion of carbon and nitrogen along the postcombustion chamber (PCC) in a 0.15 MWₜₕ CFB test platform. By ultimate analysis of fly ash and gas components an ...
DOI:
10.1021/acs.energyfuels.0c03423