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1. Nutritional condition determines behavioral response of nestling Black-browed albatrosses to a shy-bold continuum test

Author:
Morandini, Virginia; Ferrer, Miguel
Source:
Ethology, ecology & evolution 2019 v.31 no.3 pp. 266-276
ISSN:
1828-7131
Subject:
urea,   etc   ; blood; nestlings; nutritional status;     Show all 4 Subjects
Abstract:
... We used biochemical analyses of blood to quantify nutritional status and a standardized test to measure the response to a novel object (bold-shy test). Our aim was to examine the relationship between nutritional status and behavioral responses in nestlings of Black-browed albatrosses (Thalassarche melanophrys). A total of 66 nestlings from Saunders Island (Falkland) were analyzed. Around 41% of th ...
DOI:
10.1080/03949370.2019.1592229

2. Effect of particle size, die rotary speed and amount of urea on physical properties of the produced pellet

Author:
Amiri, H.; Kianmehr, M. H.; Arabhosseini, A.
Source:
International journal of environmental science and technology 2019 v.16 no.4 pp. 2059-2068
ISSN:
1735-1472
Subject:
urea; urea fertilizers,   etc   ; absorption; composts; durability; energy; leaching; mixing; nitrogen; nutrient uptake; particle size; pellets;     Show all 12 Subjects
Abstract:
... Provided pellet by mixing of urea and compost is a kind of nitrogenous fertilizer with gradual release that reduces leaching losses and increases gradual absorption of nitrogen during the growing long season. In this study, the characteristics of the produced pellet such as durability, strength and moisture absorption were examined at two density levels (low and high), three ratio levels of compos ...
DOI:
10.1007/s13762-017-1627-1

3. Urea-Linked Covalent Organic Frameworks

Author:
Zhao, Chenfei; Diercks, Christian S.; Zhu, Chenhui; Hanikel, Nikita; Pei, Xiaokun; Yaghi, Omar M.
Source:
Journal of the American Chemical Society 2018 v.140 no.48 pp. 16438-16441
ISSN:
1520-5126
Subject:
urea,   etc   ; hydrogen bonding;     Show all 2 Subject
Abstract:
... 2D covalent organic frameworks (COFs) with flexible urea linkages have been synthesized by condensation of 1,3,5-triformylphloroglucinol (TFP) with 1,4-phenylenediurea (BDU) or 1,1′-(3,3′-dimethyl-[1,1′-biphenyl]-4,4′-diyl)diurea (DMBDU). The resulting COF-117 and COF-118 undergo reversible structural dynamics within their layers, in response to inclusion and removal of guest molecules, emanating ...
DOI:
10.1021/jacs.8b10612

4. Transition-metal-free C–H amidation and chlorination: synthesis of N/N′-mono-substituted imidazopyridin-2-ones from N-pyridyl-N-hydroxylamine intermediates

Author:
Lee, Katarzyna N.; Spiegowski, Dominique N.; Lee, Johnny W.; Lim, Sanghyun; Zhao, Fuhua; Ngai, Ming-Yu
Source:
Chemical communications 2018 v.54 no.50 pp. 6935-6938
ISSN:
1364-548X
Subject:
urea,   etc   ; chlorination; moieties;     Show all 3 Subjects
Abstract:
... Non-symmetric 1,3-substituted imidazopyridin-2-ones are a common structural scaffold found among many biologically active molecules. Herein we report an efficient, mild, and transition-metal free C–H amidation strategy to access such a pyrido-fused cyclic urea framework in good yields and with a broad functional group tolerance. ...
DOI:
10.1039/c8cc02425a

5. Correction to: Scenario modeling of ammonia emissions from surface applied urea under temperate conditions: application effects and model comparison

Author:
Pacholski, Andreas; Doehler, Johannes; Schmidhalter, Urs; Kreuter, Thomas
Source:
Nutrient cycling in agroecosystems 2018 v.110 no.1 pp. 195-196
ISSN:
1385-1314
Subject:
urea,   etc   ; ammonia; emissions; models;     Show all 4 Subjects
Abstract:
... The captions of figures 3–6 in the original publication are misplaced. The correct figure captions are as follows. ...
DOI:
10.1007/s10705-017-9890-6

6. Effectiveness and mechanism of carbamide/fly ash cenosphere with bilayer spherical shell structure as explosion suppressant of coal dust

Author:
Wang, Xiang; Zhang, Yansong; Liu, Bo; Liang, Peng; Zhang, Yaqing
Source:
Journal of hazardous materials 2019 v.365 pp. 555-564
ISSN:
0304-3894
Subject:
urea,   etc   ; coal; dust; explosions; fly ash; freeze drying; particle size;     Show all 7 Subjects
Abstract:
... This study aims to eliminate or suppress explosion accidents in powder preparation and storage systems of coal dust. The modified fly ash cenosphere (FAC) was used as an inner spherical shell carrier with carbamide impregnated. Carbamide/FAC composite suppressant with bilayer spherical shell was prepared by vacuum freeze-drying. The flame propagation and explosion performances of coal were tested, ...
DOI:
10.1016/j.jhazmat.2018.11.044

7. Synergetic pore structure optimization and nitrogen doping of 3D porous graphene for high performance lithium sulfur battery

Author:
Cheng, Dongdong; Wu, Pingping; Wang, Jingwen; Tang, Xingwei; An, Tong; Zhou, Han; Zhang, Di; Fan, Tongxiang
Source:
Carbon 2019 v.143 pp. 869-877
ISSN:
0008-6223
Subject:
urea,   etc   ; batteries; electrochemistry; graphene; lithium; nitrogen; porosity; sulfur;     Show all 8 Subjects
Abstract:
... Synthesis of multifunctional sulfur host material with comprehensive abilities of sulfur accommodation, electron/ion transfer and polysulfides confining is vital and challenging to bring the theoretical merits of lithium sulfur battery to practical application. Herein, a facile strategy is demonstrated to prepare 3-dimensional hierarchical porous nitrogen doped graphene as a sulfur host material f ...
DOI:
10.1016/j.carbon.2018.11.032

8. Visual and Precise Detection of pH Values under Extreme Acidic and Strong Basic Environments by Cellulose-Based Superior Sensor

Author:
Nawaz, Haq; Tian, Weiguo; Zhang, Jinming; Jia, Ruonan; Yang, Tiantian; Yu, Jian; Zhang, Jun
Source:
Analytical chemistry 2019 v.91 no.4 pp. 3085-3092
ISSN:
1520-6882
Subject:
urea,   etc   ; acidity; color; dyes; environmental monitoring; fluorescence; moieties; pH;     Show all 8 Subjects
Abstract:
... Precise determination of pH values with an instrument-free mode is challenging and practical in industry processes, life science, and environmental monitoring. Here, taking advantage of the intramolecular charge transfer process, we construct a cellulose-based superior pH sensor, Phen-MDI-CA, which contains a highly sensitive, pH-responsive, and extended conjugation structure by combining phenanth ...
DOI:
10.1021/acs.analchem.8b05554

9. Hydrogen-rich syngas production by reforming of ethanol blended with aqueous urea using a thermodynamic analysis

Author:
Wu, Horng-Wen; Lin, Ke-Wei
Source:
Energy 2019 v.166 pp. 541-551
ISSN:
0360-5442
Subject:
urea,   etc   ; endothermy; ethanol; steam; synthesis gas; temperature; thermodynamics;     Show all 7 Subjects
Abstract:
... This study presents a new concept of the aqueous urea solution (AUS) to replace pure water and uses a thermodynamic analysis to compare the characteristics of steam and autothermal reforming of ethanol with/without AUS. The results show that hydrogen-rich syngas production under steam reforming of ethanol (SRE) with the blended AUS is higher than that under the pure steam. Under autothermal reform ...
DOI:
10.1016/j.energy.2018.10.122

10. Molten salt synthesis of Co-entrapped, N-doped porous carbon from various nitrogen precursors as efficient electrocatalysts for hydrogen evolution

Author:
Sun, Xue; Tang, Duihai; Zhang, Wenting; Li, Kuo; Qiao, Zhen-An; Liu, Yunling; Liang, Daxin; Zhu, Junjiang; Zhao, Zhen
Source:
Journal of materials science 2019 v.54 no.1 pp. 638-647
ISSN:
0022-2461
Subject:
urea,   etc   ; carbon; dicyandiamide; glucose; histidine; hydrogen production; nitrogen; surface area;     Show all 8 Subjects
Abstract:
... We synthesized a variety of Co-entrapped, N-doped porous carbon materials via a molten salt process. Dicyandiamide, urea, guanidine hydrochloride, and histidine were used as the nitrogen precursors. Glucose and ZnCl₂ were used as carbon precursor and template, respectively. The nitrogen precursors greatly affect the porous structures of the final samples and thus the electrocatalytic activities to ...
DOI:
10.1007/s10853-018-2852-9

11. Urea dynamics during Lake Taihu cyanobacterial blooms in China

Author:
Lu, Kaijun; Liu, Zhanfei; Dai, Ruihua; Gardner, Wayne S.
Source:
Harmful algae 2019 v.84 pp. 233-243
ISSN:
1568-9883
Subject:
urea; urea nitrogen,   etc   ; Microcystis; ammonium; bacteria; bacterial communities; community structure; fertilizers; freshwater lakes; genes; nitrogen; poisonous algae; prediction; China;     Show all 14 Subjects
Abstract:
... Lake Taihu, the third largest freshwater lake in China, suffers from harmful cyanobacteria blooms caused by Microcystis spp., which do not fix nitrogen (N). Reduced N (i.e., NH4+, urea and other labile organic N compounds) is an important factor affecting the growth of Microcystis. As the world use of urea as fertilizer has escalated during the past decades, an understanding of how urea cycling re ...
DOI:
10.1016/j.hal.2019.03.010

12. Responses of litter decomposition and nutrient release of Bothriochloa ischaemum to soil petroleum contamination and nitrogen fertilization

Author:
Zhang, X.; Liu, Z.
Source:
International journal of environmental science and technology 2019 v.16 no.2 pp. 719-728
ISSN:
1735-1472
Subject:
urea; urea fertilizers,   etc   ; Bothriochloa ischaemum; ambient temperature; fertilizer application; iron; nitrogen; petroleum; phytoremediation; polluted soils; soil water; zinc;     Show all 12 Subjects
Abstract:
... To assess the effects of petroleum contamination or fertilization with nitrogenous fertilizer in contaminated soil on the litter decomposition of Bothriochloa ischaemum, a phytoremediating species, its litter was placed in litterbags and buried in uncontaminated soil, and petroleum-contaminated soil with and without urea fertilization (petroleum concentration: 45 g/kg, the ratio of soil C/N was ad ...
DOI:
10.1007/s13762-018-1727-6

13. Effects of Bentonite Application and Urea Fertilization Time on Growth, Development and Nitrate Accumulation in Spinach (Spinacia oleraceae L.)

Author:
Bandian, Leila; Nemati, Hosein; Moghaddam, Mohammad
Source:
Communications in soil science and plant analysis 2019 v.50 no.1 pp. 1-9
ISSN:
1532-2416
Subject:
urea; urea fertilizers,   etc   ; Spinacia oleracea; bentonite; fertilizer application; humans; nitrates; nitrites; oxalic acid; planting; risk; soil; sowing date; spinach;     Show all 14 Subjects
Abstract:
... Under excessive application of nitrogen fertilizer, vegetables can accumulate high levels of nitrate in their vegetative body and, when consumed by living organisms, pose serious health-related risks for humans. Regarding such problems, it is necessary to minimize the accumulation of nitrate in leafy vegetables. Therefore, a pot experiment was conducted to evaluate bentonite levels (0, 20, 40, 60, ...
DOI:
10.1080/00103624.2018.1538373

14. Biochemical effects of banding limit the benefits of nitrification inhibition and controlled-release technology in the fertosphere of high N-input systems

Author:
Janke, Chelsea K.; Fujinuma, Ryosuke; Moody, Phil; Bell, Michael J.
Source:
Soil research 2019 v.57 no.1 pp. 28-40
ISSN:
1838-675X
Subject:
polymer-coated urea; urea,   etc   ; ammonia; ammonium; buffering capacity; clay fraction; granules; hydrolysis; nitrification; nitrification inhibitors; nitrogen; pH; polymers; sugarcane;     Show all 14 Subjects
Abstract:
... Enhanced efficiency fertilisers (EEFs) may have an important role in improving nitrogen (N) use efficiency in agricultural systems. The performance of EEFs when applied by broadcasting and incorporation is well documented; however, little information is available for sub-surface banded N-fertiliser. This study aimed to determine the effectiveness of EEFs within the fertosphere in several soils. Th ...
DOI:
10.1071/SR18211

15. Improving Ambipolar Semiconducting Properties of Thiazole-Flanked Diketopyrrolopyrrole-Based Terpolymers by Incorporating Urea Groups in the Side-Chains

Author:
Ma, Jing; Liu, Zitong; Yao, Jingjing; Wang, Zhijie; Zhang, Guanxin; Zhang, Xisha; Zhang, Deqing
Source:
Macromolecules 2018 v.51 no.15 pp. 6003-6010
ISSN:
1520-5835
Subject:
urea,   etc   ; hydrogen bonding; microstructure; polymers;     Show all 4 Subjects
Abstract:
... Two new ambipolar thiazole-flanked diketopyrrolopyrrole-based polymers pDPPTz2T-1 and pDPPTz2T-2 with urea-containing linear side-chains were prepared. The formation of hydrogen bonding enhanced the ambipolar semiconducting properties, including mobilities and on/off ratios. The average mobilities (hole and electron) of pDPPTz2T-2 were 25 and 3 times higher than those of pDPPTz2T without urea grou ...
DOI:
10.1021/acs.macromol.8b01020

16. HMF in multicomponent reactions: utilization of 5-hydroxymethylfurfural (HMF) in the Biginelli reaction

Author:
Fan, Weigang; Queneau, Yves; Popowycz, Florence
Source:
Green chemistry 2018 v.20 no.2 pp. 485-492
ISSN:
1463-9270
Subject:
urea,   etc   ; furfural; green chemistry; hydroxymethylfurfural;     Show all 4 Subjects
Abstract:
... The use of the renewable platform molecule 5-hydroxymethylfurfural (HMF) in the multi-component Biginelli reaction has been investigated. Multicomponent reactions (MCR) using HMF offer straightforward access to novel fine chemicals. However, the peculiar reactivity and lower stability of HMF have limited its use in such strategies. In this paper, we report our results on the use of HMF in 3-compon ...
DOI:
10.1039/c7gc03425c

17. Direct tracing of NH3 and N2O emissions associated with urea fertilization approaches, using static incubation cells

Author:
Kira, Oz; Shaviv, Avi; Dubowski, Yael
Source:
The Science of the total environment 2019 v.661 pp. 75-85
ISSN:
0048-9697
Subject:
urea; urea fertilizers; urea nitrogen,   etc   ; ammonia; crop production; environmental factors; fertilizer rates; greenhouse gas emissions; loess; nitrification; nitrogen; nitrous oxide; pH; sandy loam soils; soil sampling; spectrometers; urease inhibitors;     Show all 17 Subjects
Abstract:
... Nitrogen fertilization contributes significantly to crop production globally. However, low efficiency application management approaches lead to substantial N losses of which ammonia and nitrous oxide are known as environmental threats. Urea, the largest N fertilization source globally, is associated with high ammonia losses. A large variety of application modes are practiced under different enviro ...
DOI:
10.1016/j.scitotenv.2019.01.128

18. Optimized tuning of rosin adduct with maleic anhydride for smart applications in controlled and targeted delivery of urea for higher plant’s uptake and growth efficiency

Author:
Mumtaz, Irsa; Majeed, Zahid; Ajab, Zainab; Ahmad, Basharat; Khurshid, Kiran; Mubashir, Muhammad
Source:
Industrial crops and products 2019 v.133 pp. 395-408
ISSN:
0926-6690
Subject:
urea; urea fertilizers,   etc   ; agricultural productivity; chlorophyll; clay loam soils; corn; growth performance; light microscopy; maleic anhydrides; pollution; rosin; slow-release fertilizers; spraying; temperature; texture; water solubility;     Show all 16 Subjects
Abstract:
... Conventional urea is lost due to its high water solubility and microbial transformations which results low agriculture productivity and environmental pollution. To solve these problems, rosin adduct-coated controlled release urea fertilizer (RA-CRUF) was prepared. Properties of rosin adduct with maleic anhydride were optimized during synthesis by varying the reaction temperature (120, 140 and 160  ...
DOI:
10.1016/j.indcrop.2019.02.036

19. Technical and environmental assessment of coated urea production with a natural polymeric suspension in spouted bed to reduce nitrogen losses

Author:
da Costa, Tamíris Pacheco; Westphalen, Gisele; Nora, Fabiola Balzan Dalla; de Zorzi Silva, Barbara; Rosa, Gabriela Silveira da
Source:
Journal of cleaner production 2019 v.222 pp. 324-334
ISSN:
0959-6526
Subject:
urea; urea fertilizers,   etc   ; air temperature; environmental assessment; environmental impact; environmental performance; fertilizer application; greenhouse gas emissions; leaching; life cycle assessment; nitrogen; polymers; volatilization;     Show all 13 Subjects
Abstract:
... Urea is the most used nitrogen fertilizer in the world, but should be supplied to the plants in a controlled way to make it as efficient as possible. Otherwise, nitrogen losses due to volatilization and leaching can reach up to 70%. The production of coated urea with slow-release polymers can be a good alternative not just to reduce the nitrogen losses but also to avoid the greenhouse gases emissi ...
DOI:
10.1016/j.jclepro.2019.03.069

20. A low-cost, portable and easy-operated salivary urea sensor for point-of-care application

Author:
Wang, Kuan-Hsun; Hsieh, Ju-Chun; Chen, Chang-Chiang; Zan, Hsiao-Wen; Meng, Hsin-Fei; Kuo, Sheng-Yu; Nguyễn, Minh Trâm Ngọc
Source:
Biosensors & bioelectronics 2019 v.132 pp. 352-359
ISSN:
0956-5663
Subject:
urea; urea nitrogen,   etc   ; biomarkers; biosensors; blood; cadmium; calibration; clinical trials; kidney diseases; light emitting diodes; optical fibers; pH; patients; point-of-care systems; saliva; urease;     Show all 16 Subjects
Abstract:
... Salivary urea was reported to be a useful biomarker to reflect the blood urea nitrogen in chronic kidney disease patients. However, as a new biomarker, enormous clinical trials are required to define the intended-use and to verify the specification. In this report, we demonstrated a low-cost easy-operated real-time sensing system (optical fiber-urea-sensing, OFUS, system) to detect salivary urea. ...
DOI:
10.1016/j.bios.2019.03.007