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1. Green, rapid and efficient synthesis of new antibacterial pyridopyrimidinone mediated by eutectic mixture of Urea/CuCl2

Author:
Riadi, Yassine
Source:
Sustainable chemistry and pharmacy 2020 v.15 pp. 100233
ISSN:
2352-5541
Subject:
urea,   etc   ; catalysts; green chemistry; microwave radiation; solvents;     Show all 5 Subjects
Abstract:
... An eco-friendly, efficient and green one-pot multicomponent preparation of pyridopyrimidine is reported. A mixture of urea/CuCl₂ was prepared and used as efficient catalyst to synthesize a various derivative of pyridopyrimidine with excellent yields in short times of reaction using microwave irradiation. All product were obtained with excellent yields (94-98%) in short time of reaction (few minute ...
DOI:
10.1016/j.scp.2020.100233

2. High throughput covalent immobilization process for improvement of shelf-life, operational cycles, relative activity in organic media and enzymatic kinetics of urease and its application for urea removal from water samples

Author:
Hormozi Jangi, Saeed Reza; Akhond, Morteza; Dehghani, Zahra
Source:
Process biochemistry 2020 v.90 pp. 102-112
ISSN:
1359-5113
Subject:
urea,   etc   ; catalytic activity; pH; shelf life; urease;     Show all 5 Subjects
Abstract:
... High throughput covalent urease immobilization was performed through the amide bond formation between the urease and the amino-functional MNPs. The enzyme’s performances, including shelf-life, reusability, enzymatic kinetics, and the enzyme relative activity in organic media was improved. At optimal conditions, the immobilization efficiency was calculated about 95.0% with keeping 94.7% of the urea ...
DOI:
10.1016/j.procbio.2019.11.001

3. Superstructure Reaction Network Design for the Synthesis of Biobased Sustainable Nitrogen-Containing Polymers

Author:
Savage, Thomas R.; Zhang, Dongda
Source:
Industrial & engineering chemistry process design and development 2020 v.59 no.10 pp. 4688-4697
ISSN:
1520-5045
Subject:
urea formaldehyde,   etc   ; biomass; hydrogen; nitrogen; nylon; wastes;     Show all 6 Subjects
Abstract:
... Biomass-derived polymer production processes have been extensively studied to substitute petrochemical-based polymer synthesis routes. However, previous research predominantly focused on the synthesis of nitrogen-free polymers. Therefore, a novel superstructure reaction network was constructed in this study to convert different types of biomass waste into a range of commercial nitrogen-containing ...
DOI:
10.1021/acs.iecr.9b06511

4. Particle number balance approach for simulation of a multi-chamber fluidized bed urea granulator; Modeling and validation

Author:
Nemati, H.; Shekoohi, S.A.
Source:
Powder technology 2020 v.369 pp. 96-105
ISSN:
0032-5910
Subject:
urea; urea fertilizers,   etc   ; coatings; equations; fluidized beds; mass density; model validation; simulation models;     Show all 8 Subjects
Abstract:
... In the present work, a model was proposed to simulate the growth in an industrial multi-chamber fluidized bed granulator under steady-state condition. To simulate the growth, it was assumed the coating is the only growth mechanism. Mass balance, as well as particle number balance (PNB), was considered in the simulation. Despite previous works, it was not assumed that particles in each chamber are ...
DOI:
10.1016/j.powtec.2020.05.010

5. Effect of controlled-release urea on heavy metal mobility in a multimetal-contaminated soil

Author:
XU, Chao; XIANG, Qian; ZHU, Qihong; ZHU, Hanhua; HUANG, Daoyou; ZHANG, Yangzhu
Source:
Pedosphere 2020 v.30 no.2 pp. 263-271
ISSN:
1002-0160
Subject:
polymer-coated urea; sulfur-coated urea; urea,   etc   ; acid soils; ammonium; cadmium; copper; dryland farming; heavy metals; lead; polluted soils; soil pH; sulfates; water solubility; zinc;     Show all 15 Subjects
Abstract:
... Controlled-release N fertilizers can affect the availability of heavy metals in the contaminated paddy soil. A soil incubation experiment was conducted to investigate the effects of prilled urea (PU), S-coated urea (SCU), and polymer-coated urea (PCU) on the solubility and availability of heavy metals Cd, Pb, Cu, and Zn in a multimetal-contaminated soil. The results showed that the application of ...
DOI:
10.1016/S1002-0160(17)60467-3

6. Adaptation of a continuous, calorimetric kinetic assay to study the agmatinase-catalyzed hydrolytic reaction

Author:
Wilson, Liam A.; Garcia, David; Pedroso, Marcelo Monteiro; Schulz, Benjamin L.; Guddat, Luke W.; Schenk, Gerhard
Source:
Analytical biochemistry 2020 v.595 pp. 113618
ISSN:
0003-2697
Subject:
urea,   etc   ; agmatine; calorimetry; catalytic activity; colorimetry; enzymes; putrescine; titration;     Show all 8 Subjects
Abstract:
... Ureohydrolases are members of the metallohydrolase family of enzymes. Here, a simple continuous assay for agmatinase (AGM) activity was established by following the degradation of agmatine to urea and putrescine using isothermal titration calorimetry (ITC). ITC is particularly useful for kinetic assays when substrates of interest do not possess suitable chromophores that facilitate the continuous ...
DOI:
10.1016/j.ab.2020.113618

7. A green and practical reduction of N-(4-chlorophenyl)-2-nitroaniline and its derivatives to corresponding N-substituted-benzene-1,2-diamines using thiourea dioxide

Author:
Zhong, Cong-Shan; Cui, Jian-Lan; Yu, Si-Yuan; Wang, Xiao; Wang, Ning
Source:
Tetrahedron letters 2020 v.61 no.11 pp. 151599
ISSN:
0040-4039
Subject:
urea,   etc   ; chemical reactions; chemical structure; filtration; sodium hydroxide; thiourea;     Show all 6 Subjects
Abstract:
... A new effective approach for synthesizing diverse N-substituted-benzene-1,2-diamines is reported. The treatment of N-substituted-2-nitroanilines with thiourea dioxide in the presence of sodium hydroxide efficiently formed the corresponding N-substituted-benzene-1,2-diamines, including N-(4-chlorophenyl)benzene-1,2-diamine with a good yield of 94%. The by-product is environmentally-friendly urea an ...
DOI:
10.1016/j.tetlet.2020.151599

8. Nutrient diffusion control of fertilizer granules coated with a gradient hydrophobic film

Author:
Dai, Congrun; Yang, Ling; Xie, Jiuren; Wang, Ting-Jie
Source:
Colloids and surfaces 2020 v.588 pp. 124361
ISSN:
0927-7757
Subject:
urea,   etc   ; coatings; composite polymers; fertilizers; granules; hydrophilicity; hydrophobicity; polydimethylsiloxane; polyurethanes;     Show all 9 Subjects
Abstract:
... A gradient hydrophobic film was prepared to improve the controlled release performance of film-coated fertilizers. A polyurethane (PU) was copolymerized with hydroxypropyl-terminated polydimethylsiloxane (HP-PDMS) at different ratios to produce a film with different levels of hydrophobicity. A film with a gradient hydrophobicity was prepared by successively coating a copolymer of PDMS/PU at differ ...
DOI:
10.1016/j.colsurfa.2019.124361

9. Room-temperature dissolution and chemical modification of cellulose in aqueous tetraethylammonium hydroxide–carbamide solutions

Author:
Sirviö, Juho Antti; Heiskanen, Juha P.
Source:
Cellulose 2020 v.27 no.4 pp. 1933-1950
ISSN:
0969-0239
Subject:
urea,   etc   ; ambient temperature; cellulose; chlorides; solvents; tetraethylammonium compounds;     Show all 6 Subjects
Abstract:
... The room-temperature dissolution of cellulose in aqueous tetraethylammonium hydroxide (TEAOH) in the presence of carbamides (ureas) was investigated. Without carbamide, 35 wt% TEAOH was able to dissolve cellulose (microcrystalline cellulose) up to 3 wt%, whereas carbamides—such as urea, N-methylurea, N-ethylurea, 1,3-dimethylurea, and imidazolidone—were able to improve the dissolution of cellulose ...
DOI:
10.1007/s10570-019-02907-x

10. Self-Integratable, Healable, and Stretchable Electroluminescent Device Fabricated via Dynamic Urea Bonds Equipped in Polyurethane

Author:
Shin, Yoo Bin; Ju, Yun Hee; Lee, Hee-Jin; Han, Chul Jong; Lee, Cheul-Ro; Kim, Youngmin; Kim, Jong-Woong
Source:
ACS applied materials & interfaces 2020 v.12 no.9 pp. 10949-10958
ISSN:
1944-8252
Subject:
urea,   etc   ; cutting; electrodes; glass transition temperature; nanosilver; nanowires; polyurethanes;     Show all 7 Subjects
Abstract:
... Reversible bonding between polymer chains has been used primarily to induce self-healing of damaged polymers. Inspired by the dynamic nature of such bonding, we have developed a polyurethane equipped with dynamic urea bonds (PEDUB) that has high strength sufficient to make it be freestanding and have a healing capability and self-bonding property. This allowed subsequent heterogeneous multicompone ...
DOI:
10.1021/acsami.9b21789

11. Temperature responsive self-assembled hydroxybutyl chitosan nanohydrogel based on homogeneous reaction for smart window

Author:
Bi, Shichao; Feng, Chao; Wang, Mengyang; Kong, Ming; Liu, Ya; Cheng, Xiaojie; Wang, Xuanpeng; Chen, Xiguang
Source:
Carbohydrate polymers 2020 v.229 pp. 115557
ISSN:
0144-8617
Subject:
urea,   etc   ; biodegradability; chitosan; coagulation; light; phase transition; potassium hydroxide; temperature;     Show all 8 Subjects
Abstract:
... Chitosan (CS) based self-assembled nanohydrogels are considered as promising platform for biomedicine, petrochemical, agricultural and food applications due to their unique biodegradability, nano-interface effect, and intelligent responsiveness. However, the most CS derivatives are prepared in heterogeneous system, which is unstable and environmentally unfriendly. In this work, a series of hydroxy ...
DOI:
10.1016/j.carbpol.2019.115557

12. Comparing ammonia volatilization between conventional and slow-release nitrogen fertilizers in paddy fields in the Taihu Lake region

Author:
Liu, Xiaodong; Chen, Luying; Hua, Zulin; Mei, Shengcheng; Wang, Peng; Wang, Shuwei
Source:
Environmental science and pollution research international 2020 v.27 no.8 pp. 8386-8394
ISSN:
0944-1344
Subject:
sulfur-coated urea; urea,   etc   ; ammonia; ammonium; fertilizer rates; field experimentation; lakes; nutrient use efficiency; pH; paddies; pollution; rain; volatilization;     Show all 13 Subjects
Abstract:
... Pollution arising from ammonia volatilization in paddy fields could be reduced by using slow-release nitrogen fertilizers. In recent years, slow-release nitrogen fertilizers have been commonly used to replace conventional nitrogen fertilizers in the Taihu Lake region to reduce ammonia volatilization and improve nitrogen-use efficiency. To compare ammonia volatilization losses and examine the effec ...
DOI:
10.1007/s11356-019-07536-2

13. Full spectrum core–shell phosphors under ultraviolet excitation

Author:
Ding, Hui; Qin, Haiming; Feng, Shaowei; Hua, Hui; Du, Qiping; Jiang, Hongtao; Jiang, Jun; Jiang, Haochuan
Source:
Chemical communications 2019 v.55 no.81 pp. 12188-12191
ISSN:
1364-548X
Subject:
urea,   etc   ; chemical reactions; photons; wavelengths;     Show all 4 Subjects
Abstract:
... A YAG:Ce/MgY₄Si₃O₁₃:Ce–Y₂O₃:Eu core–shell structure was designed and accomplished via a urea homogeneous precipitation method. The as prepared phosphors can emit photons with a broad range of wavelengths from 340 nm to 700 nm under excitation light of 330 nm. The internal quantum efficiency can reach up to 68%. ...
DOI:
10.1039/c9cc04827h

14. Dipole-Induced Rectification Across AgᵀS/SAM//Ga₂O₃/EGaIn Junctions

Author:
Baghbanzadeh, Mostafa; Belding, Lee; Yuan, Li; Park, Junwoo; Al-Sayah, Mohammad H.; Bowers, Carleen M.; Whitesides, George M.
Source:
Journal of the American Chemical Society 2019 v.141 no.22 pp. 8969-8980
ISSN:
1520-5126
Subject:
urea,   etc   ; electrodes; moieties; silver; thiourea;     Show all 5 Subjects
Abstract:
... This Article describes the relationship between molecular structure, and the rectification of tunneling current, in tunneling junctions based on self-assembled monolayers (SAMs). Molecular dipoles from simple organic functional groups (amide, urea, and thiourea) were introduced into junctions with the structure AgᵀS/S(CH₂)ₙR(CH₂)ₘCH₃//Ga₂O₃/EGaIn. Here, R is an n-alkyl fragment (−CH₂−)₂ ₒᵣ ₃, an a ...
DOI:
10.1021/jacs.9b02891

15. 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

16. Restricted nitrous oxide emissions by ammonia oxidizers in two agricultural soils following excessive urea fertilization

Author:
Chen, Zhaoming; Wang, Qiang; Zhao, Jun; Chen, Yudong; Wang, Huoyan; Ma, Junwei; Zou, Ping; Bao, Li
Source:
Journal of soils and sediments 2020 v.20 no.3 pp. 1502-1512
ISSN:
1439-0108
Subject:
urea; urea fertilizers; urea nitrogen,   etc   ; Anthrosols; Archaea; agricultural soils; ammonia; ammonium; bacteria; climate change; fertilizer application; greenhouse gas emissions; nitrification; nitrogen; nitrous oxide; nutrient use efficiency; osmotic stress; oxidants; oxidation; quantitative polymerase chain reaction; soil ecology; soil function;     Show all 22 Subjects
Abstract:
... PURPOSE: Nitrogen (N) fertilizer placement in bands is a widely accepted agricultural practice to increase N use efficiency. An excessive ammonium concentration in a fertilizer band can increase osmotic stress on ammonia oxidizers and potentially affect nitrification and resultant nitrous oxide (N₂O) emissions, which is of great significance for soil function and climate change. The objectivity of ...
DOI:
10.1007/s11368-019-02479-0

17. Porous defective carbon nitride obtained by a universal method for photocatalytic hydrogen production from water splitting

Author:
Jing, Liquan; Wang, Duidui; Xu, Yuanguo; Xie, Meng; Yan, Jia; He, Minqiang; Song, Zhilong; Xu, Hui; Li, Huaming
Source:
Journal of colloid and interface science 2020 v.566 pp. 171-182
ISSN:
0021-9797
Subject:
urea; urea nitrate,   etc   ; carbon nitride; free radicals; grinding; hydrogen; hydrogen production; irradiation; light; lighting; melamine; oxygen; photocatalysis; pollutants; polymers; raw materials; surface area;     Show all 17 Subjects
Abstract:
... For the first time, herein this work, we have developed an effective and adaptable method to introduce defects onto the polymeric carbon nitride by simply grinding urea with urea nitrate which resulting new carbon nitride composite (UNU-C₃N₄) and melamine with urea nitrate which resulting new carbon nitride composite (UNM-C₃N₄). The UNU-C₃N₄ reveals high performance towards photocatalytic hydrogen ...
DOI:
10.1016/j.jcis.2020.01.044

18. Effect of combining urea fertilizer with P and K fertilizers on the efficacy of urease inhibitors under different storage conditions

Author:
Sha, Zhipeng; Lv, Tiantian; Staal, Maarten; Ma, Xin; Wen, Zhang; Li, Qianqian; Pasda, Gregor; Misselbrook, Tom; Liu, Xuejun
Source:
Journal of soils and sediments 2020 v.20 no.4 pp. 2130-2140
ISSN:
1439-0108
Subject:
urea; urea fertilizers,   etc   ; ammonia; compound fertilizers; diammonium phosphate; enzymes; magnesium sulfate; nitrogen; phosphorus; phosphorus fertilizers; potassium; potassium fertilizers; soil; soil treatment; storage temperature; storage time; urease inhibitors; volatilization;     Show all 18 Subjects
Abstract:
... PURPOSE: Urease inhibitors provide a simple solution to mitigate ammonia loss from fertilized soil. Consumption of bulk blend fertilizers and compound fertilizers were increased in recent year and its enhanced efficiency and stabilized techniques were urgently required. However, it is essentially unknown if and how the efficacy of urease inhibitors is influenced by the inclusion of phosphorus (P) ...
DOI:
10.1007/s11368-019-02534-w

19. Ammonia emissions from irrigated pastures on Solonetz in Victoria, Australia

Author:
Denmead, Owen Thomas; Bai, Mei; Turner, Debra; Li, Yong; Edis, Robert; Chen, Deli
Source:
Geoderma regional 2020 v.20 pp. e00254
ISSN:
2352-0094
Subject:
urea; urea nitrogen,   etc   ; Solonetz; ammonia; autumn; dairy cattle; dairy farming; emissions factor; excreta; gas emissions; grazing; herds; irrigated pastures; irrigation; models; nitrogen; samplers; summer; volatilization; Victoria (Australia);     Show all 20 Subjects
Abstract:
... This paper reports ammonia (NH₃) emissions from irrigated, fertilized pastures grazed intensively by dairy cattle in Victoria, Australia. Irrigation bays (65 × 365 m) were grazed in rotation by 315 dairy cattle and daily emissions were measured in summer and autumn. After grazing for a few days, the bays were fertilized with urea at 50 kg N ha⁻¹ and irrigated with 50 mm of water. Passive NH₃ sampl ...
DOI:
10.1016/j.geodrs.2020.e00254

20. Automated colorimetric determination of nanomolar urea in seawater by gas-segmented continuous flow analysis using a liquid waveguide capillary cell

Author:
Takeda, Noriko; Hashihama, Fuminori; Kanda, Jota
Source:
Talanta 2020 v.208 pp. 120371
ISSN:
0039-9140
Subject:
urea; urea nitrogen,   etc   ; absorbance; automation; cetyltrimethylammonium bromide; colorimetry; detection limit; diacetyl; liquids; octoxynol; seawater; sodium chloride; sodium dodecyl sulfate; surfactants; urease;     Show all 15 Subjects
Abstract:
... A sensitive automated colorimetric method for the determination of nanomolar concentration of urea in seawater is presented. The colorimetry was based on the diacetyl monoxime method and the automated system was constructed by a gas-segmented continuous flow analyzer equipped with a 100 cm path length of liquid waveguide capillary cell. The most suitable surfactant for the system was hexadecyl-tri ...
DOI:
10.1016/j.talanta.2019.120371