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urea, etc ; catalysts; catalytic activity; coordination polymers; electrodes; hydrogen; nanosheets; oxidation; Show all 8 Subjects
Abstract:
... NiOOH has been considered as the active center for urea oxidation reaction (UOR), but it remains challenging to synthesize high-performance NiOOH-based catalysts. Herein, we realize the synthesis of a high-performance NiOOH-based catalyst through in-situ transformation from the NiMn-based metal–organic framework to NiMnOOH. X-ray photoelectron spectroscopy characterization shows that the Ni³⁺/Ni²⁺ ...
urea, etc ; density functional theory; electric potential difference; hydrogen production; nanoparticles; nanorods; oxidation; oxygen production; Show all 8 Subjects
Abstract:
... Electrocatalytic urea oxidation (UOR) has attracted significant interest as a promising anodic half-reaction to replace sluggish oxygen evolution reaction (OER) toward water splitting. However, the activation and decomposition of urea molecule maintains a challenge during electrocatalytic process because of its 6e⁻ oxidation procedure. Herein, Ni nanoparticles decorated NiMoOₓ nanorod (Ni/NiMoOₓ) ...
urea, etc ; carbon nitride; density functional theory; energy; graphene; hydrogen; hydrogen production; photocatalysis; photocatalysts; polymerization; wavelengths; Show all 11 Subjects
Abstract:
... As an efficient photocatalyst, graphitic carbon nitride (g-C₃N₄) has been widely used in the field of photocatalytic hydrogen production. However, how to prepare hydrogen efficiently and stably has become a challenge. Herein, we successfully realize metal-free edge modification with phenyl groups by one-step thermal polymerization of urea with 4-phenyl-3-thiosemicarbazide. Consequently, the optima ...
urea, etc ; coumarin; derivatization; electrospray ionization mass spectrometry; fluorescence; high performance liquid chromatography; tandem mass spectrometry; wavelengths; Show all 8 Subjects
Abstract:
... In this paper, we report about the application of a sensitive fluorescent derivatization reagent Coumarin151-N-Hydroxysuccinimidyl Carbamate (Cou151DSC) for amino compounds using high-performance liquid chromatography (HPLC) compatible with ultraviolet (UV), fluorescence detector (FLD) and electrospray ionization - tandem mass spectrometry (ESI-MS/MS)―positive mode. We optimized derivatization pro ...
... Agriculture lands have low fertilizer retention owing to porosity and irrigation, whereas a significant portion of fertilizer is lost through denitrification, volatilization, surface run-off, and leaching, causing losses of nutrients to air and ground/surface water. Urea fertilizer readily enhances the agricultural yield but also deteriorates the quality of fertile soils. To combat such problems, ...
... Peganum harmala L. is a traditional medicinal plant used for centuries in folk medicine. It has a wide array of therapeutic attributes, which include hypoglycemic, sedative, anti-inflammatory, and antioxidant properties. The fruit decoction of this plant was claimed by Avicenna as traditional therapy for urolithiasis. Also, P. harmala seed showed a clinical reduction in kidney stone number and siz ...
urea, etc ; activation energy; ambient temperature; cleavage (chemistry); electric potential difference; electric power; electrodes; electrolysis; foams; hydrogen production; nanomaterials; oxidation; oxygen production; Show all 13 Subjects
Abstract:
... It is urgent to develop non-noble metal electrocatalysts with both excellent activity and durable stability for H₂ production via water electrolysis. Electric energy is mainly consumed by the sluggish anodic oxygen evolution reaction (OER). The electrocatalytic urea oxidation reaction (UOR) has been regarded as a promising reaction to replace OER because of its small thermodynamic oxidation potent ...
... The environmental behavior of arsenic (As) is commonly affected by the biogeochemical processes of iron (Fe) and nitrogen (N). In this study, field experiments were conducted to explore As uptake in rice and As translation and distribution in As-contaminated iron-rich paddy soils after applying different forms of N fertilizers, including urea (CO(NH₂)₂), ammonium bicarbonate (NH₄HCO₃), nitrate of ...
urea, etc ; chromic oxide; electric potential difference; electrochemistry; electrodes; electrolysis; electron transfer; energy conversion; hydrogen; nanoparticles; nanosheets; nickel oxide; oxidation; protective effect; reaction kinetics; Show all 15 Subjects
Abstract:
... Applications of urea oxidation reaction (UOR) in various sustainable energy-conversion systems are greatly hindered by its slow kinetics. Herein, we demonstrate an in-situ confined synthesis method that produces amorphous chromium oxide confined Ni/NiO nanoparticles-assembled nanosheets (Ni/NiO@CrOₓ) with fast reaction kinetics towards UOR. The confinement effect of the in-situ generated CrOₓ over ...
urea, etc ; Escherichia coli; carbon; centrifugation; citric acid; detection limit; fluorescence; fluorescent dyes; hot water treatment; lipopolysaccharides; pH; peptides; signal-to-noise ratio; ultrafiltration; Show all 14 Subjects
Abstract:
... This study fabricated yellow-emitting CDs (Y-CDs) by hydrothermal treatment of citric acid and urea and applied them as a fluorescence turn-on platform for sensitive and selective detection of lipopolysaccharide (LPS) based on the non-shifted AIEE of peptide-stabilized CD aggregates. The designed peptide (named K3) consisting of aggregation-active and LPS-recognition units triggered the aggregatio ...
urea, etc ; carbon; carbon dioxide; catalysts; desorption; electric potential difference; electrical conductivity; electrochemistry; electrolysis; energy conversion; fuel cells; hydrogen peroxide; nanocrystals; nickel; oxidation; pollution; selenides; Show all 17 Subjects
Abstract:
... Electrochemical urea oxidation reaction (UOR) is urgently in demand for diverse energy conversion and storage device coupled with pollution treatment because of its favorable thermodynamic potential (0.37 V vs RHE) and wide distribution nature of urea, but simultaneously gravely limited by the sluggish reaction dynamics and poisoning of catalyst. Herein, dual-phased Ni₀.₈₅Se/NiSe₂ coupling with N ...
... Organic wastes, fertilizers, organominerals, and minerals contain nutrients essential to crops and contribute to increase productivity. However their use can also lead to the accumulation of copper and zinc, which changes the distribution of their fractions and enhances the risk of toxicity to plants and the environment, thereby working against the sustainable development goals. However, the effec ...
urea, etc ; Brassica oleracea var. italica; abscisic acid; broccoli; calcium; carbon dioxide; chlorophyll; glucobrassicin; leaves; nitrate reductase; nitrates; nitrogen; nutrient content; nutrient uptake; nutritive value; photosynthesis; progoitrin; salinity; salt stress; tryptophan; vegetative growth; Show all 21 Subjects
Abstract:
... Chelated mineral supplements are a combination of minerals with amino acids (AAs), putatively more efficient as fertilizers, especially for enhancing nutrient absorption. This study aimed at investigating the efficacy of foliar-applied calcium (Ca) and its complex with tryptophan to improve the vegetative growth, biochemical attributes and nutritional value of salt stressed broccoli (Brassica oler ...
Archana Mishra; Bakht Ramin Shah; Koushik Roy; Ehdaa Eltayeb Eltigani Abdelsalam; Veronika Piačková; Haq Abdul Shaik; Petr Dvořák; Josef Velíšek; Kuebutornye Felix Kofi Agbeko; Jan Mráz
... In aquaculture, the therapeutic potential of andrographolide had been beneficially documented but still restricted owing to its high dosage and low bioavailability. To maximize andrographolide's potential value in carps, we want to create an effective delivery mechanism. During the 8-week Cyprinus carpio feeding trial, we aimed to test a low dose (0.05 g kg⁻¹ or 0.005%) andrographolide-supplemente ...
... Triclosan (TCS) is a ubiquitous antimicrobial used in daily consumer products. Previous reports have shown that TCS could induce hepatotoxicity, endocrine disruption, disturbance on immune function and impaired thyroid function. Kidney is critical in the elimination of toxins, while the effects of TCS on kidney have not yet been well-characterized. The aim of the present study was to investigate t ...
urea; urea nitrogen, etc ; biochar; corn; leaves; microbial biomass; mineralization; nitrogen fertilizers; rhizosphere; soil; Show all 10 Subjects
Abstract:
... Biochar amendments regulate fertilizer nitrogen (N) transformation in soil and crop N uptake. To elucidate the effect of biochar amendment on the translocation of fertilizer N in a crop-soil system during crop growth, a maize pot experiment was conducted using an isotope tracer approach. The treatments were: without N application; ¹⁵N-labelled urea; and ¹⁵N-labeled urea plus biochar. During maize ...
... We disclose a palladium and urea ligand-mediated heteroannulation of 2-bromophenols and 1,3-dienes. This method addresses synthetic challenges present in the palladium-catalyzed heteroannulation of bifunctional reagents and olefins by engaging a diverse scope of coupling partners under a unified set of reaction conditions. Our recently developed urea ligand platform outperforms phosphine ligands t ...
urea; urea nitrogen, etc ; Triticum aestivum; environment; grain yield; plant height; wheat; zinc; zinc oxide; Show all 9 Subjects
Abstract:
... Slow release urea has been widely tested in recent past as an effective method to enhance the crop productivity with fewer environmental concerns. However, very few research studies have been performed using micronutrients as a source of slow release of urea nitrogen. A laboratory and field study were carried out to check the agronomic effects of zinc oxide nanoparticles and its bulk salt coatings ...
urea; urea fertilizers, etc ; application timing; climate; crop management; nitrogen; nutrient use efficiency; soil; tomatoes; Nepal; Show all 10 Subjects
Abstract:
... In Nepal, blanket fertilizer recommendations without considering diverse soil types, nutrient status, climate and crop management practices along with imbalanced fertilization practices by farmers, mainly “urea fertilizer,” have resulted in reduced nitrogen use efficiency (NUE) and productivity in tomato production. Optimizing the rate of nitrogen (N) fertilizer, application time and improved appl ...
polymer-coated urea; urea, etc ; Pinus elliottii; ammonium nitrogen; fertilizer rates; mortality; nitrogen; soil solution; Florida; Show all 9 Subjects
Abstract:
... Commercial pine plantations in the southern United States are commonly fertilized to enhance growth and to replenish nutrients following timber harvests or repetitive raking of pinestraw, an important secondary product. We examined the effects of pinestraw removal and fertilization on pine growth and N leaching potential in an 8‐yr‐old slash pine (Pinus elliottii Engelm.) plantation in North Flori ...