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The purpose of the study was to examine the storage and transport of NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$ions through snowpack, soils, and stream water in an acid‐sensitive alpine catchment (Tatra Mountains, Poland) during snowmelt and rain‐on‐snow events. Samples of snowpack layers, near‐surface soil horizons, and stream water were collected in the winter and snowmelt seasons of 2019. A laboratory experiment was conducted to determine the effect of temperature on the rate of soil nitrogen mineralization and nitrification. Our study has shown that snowpack is an important source of NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$ions in the catchment. As the snow melts, the release of NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$ions from snowpack occurs. A gradual and slow melting of snow starts even before the first snowmelt‐induced increase in stream discharge. NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$ions eluted from available snowpack are temporarily stored in soil, which is shown by a large increase in the concentration of water‐soluble NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$in the soil at that time. NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$ions are washed out of soils and supplied to streams during the first snowmelt event. This is demonstrated by a large increase in the stream water NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$concentration, termed an “NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$pulse.” The NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$ion is a key acid anion responsible for the acidification of the studied stream during snowmelt season, as the NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$pulse coincides with a decrease in bicarbonate alkalinity. Our field research and laboratory experiment have shown a minor role of mineralization and nitrification in NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$production in soils in the winter and NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$pulse formation in stream water during the early stages of the snowmelt season. Key Points NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$ions eluted from snowpack in winter are temporarily stored in soils; they are washed out of soils during the first snowmelt event Large supply of NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$at the beginning of snowmelt forms an NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$pulse in stream water which results in stream water acidification The mineralization and nitrification of organic nitrogen play a minor role in NO3−${\\mathrm{N}\\mathrm{O}}_{3}^{-}$production in soils in the winter season

The N form supplied to the plant, ammonium (NH 4 + ) or nitrate (NO 3 – ), is a major factor determining the impact of N nutrition on plant function and metabolic responses. We have hypothesized that the ratio of NH 4 /NO 3 supplied to cannabis plants affects the physiological function and the biosynthesis of cannabinoids and terpenoids, which are major factors in the cannabis industry. To evaluate the hypothesis we examined the impact of five supply ratios of NH 4 /NO 3 (0, 10, 30, 50, and 100% N-NH 4 + , under a uniform level of 200 mg L –1 N) on plant response. The plants were grown in pots, under controlled environment conditions. The results revealed high sensitivity of cannabinoid and terpenoid concentrations and plant function to NH 4 /NO 3 ratio, thus supporting the hypothesis. The increase in NH 4 supply generally caused an adverse response: Secondary metabolite production, inflorescence yield, plant height, inflorescence length, transpiration and photosynthesis rates, stomatal conductance, and chlorophyll content, were highest under NO 3 nutrition when no NH 4 was supplied. Ratios of 10–30% NH 4 did not substantially impair secondary metabolism and plant function, but produced smaller inflorescences and lower inflorescence yield compared with only NO 3 nutrition. Under a level of 50% NH 4 , the plants demonstrated toxicity symptoms, which appeared only at late stages of plant maturation, and 100% NH 4 induced substantial plant damage, resulting in plant death. This study demonstrates a dramatic impact of N form on cannabis plant function and production, with a 46% decrease in inflorescence yield with the increase in NH 4 supply from 0 to 50%. Yet, moderate levels of 10–30% NH 4 are suitable for medical cannabis cultivation, as they do not damage plant function and show only little adverse influence on yield and cannabinoid production. Higher NH 4 /NO 3 ratios, containing above 30% NH 4 , are not recommended since they increase the potential for a severe and fatal NH 4 toxicity damage.

The demand for solid polymer electrolytes is increasing continuously because of their better mechanical properties, stability, and strength while compared with liquid or gel electrolytes. However, the polymers are having poor ionic conductivity that can be improved by adding ionic salt during solid electrolyte production. Further, not all the electrolytes are compatible with polymers also the concentration of ionic salt beyond some limit not only decrease the ionic conductivity of solid electrolyte but also decrease the strength as well. In the present work, the mixture of two different polymers (10% PEO and 90% PVDF) is selected as the parent polymer for the production of solid polymer electrolytes. Mg(NO 3 ) 2 is used as ionic salt to increase the ionic conductivity and other properties of electrolytes. The concentration of Mg(NO 3 ) 2 is taken in 10%, 15%, and 20% (w%w) to the parent polymer, and the effects are analyzed on ionic conductivity. It is found that the addition of Mg(NO 3 ) 2 improves the ionic conductivity of electrolytes with a higher rate initially but the rate of increase of ionic conductivity decreases after 15%. Further, better thermal conduction and other properties are observed for the electrolyte having a 15% Mg(NO 3 ) 2 concentration. The detailed results are given in the present work.

The challenges in water treatment include the need for efficient removal of pollutants like nitrate, which poses significant environmental and health risks. Alumina's significance lies in its proven effectiveness as an adsorbent for nitrate removal due to its high surface area and affinity for nitrate ions. This study delves into the synthesis of differen nano-sized γ-alumina (γA1-5) employing diverse precursors and methods, including nepheline syenite, lime, aluminum hydroxide, precipitation, and hydrothermal processes at varying reaction times. Simultaneously, magnetite (Fe 3 O 4 ) nanoparticles and magnetite/γ-alumina nanocomposites (F n /γA5) were synthesized using the co-precipitation method with varying weight ratios (n). Our primary objective was to optimize γ-alumina synthesis by comparing multiple methods, shedding light on the influence of different precursors and sources. Hence, a comprehensive adsorption study was conducted to assess the materials’ efficacy in nitrate removal. This study fills gaps in the literature, providing a novel perspective through the simultaneous assessment of magnetite/alumina nanocomposites and pure alumina performance. Structural and morphological properties were studied employing XRD, FT-IR, FESEM, EDX, XRD, and VSM techniques. The conducted experiments for γA5, F 5 /γA5, and F 10 /γA5 nanocomposites showcased the optimum pH of 5 and contact time of 45 min for all samples. The influence of nitrate’s initial concentration on the removal percentage was investigated with initial concentrations of 10 ppm, 50 ppm, and 100 ppm. γA5, F 5 /γA5 and F 10 /γA5 nanocomposites had 17.3%, 55%, and 70% at 10 ppm, 18%, 55.16%, and 74% at 50 ppm, and 8.6%, 53.1%, and 63%, respectively. The results highlighted that F 10 /γA5 can be used as a remarkable adsorbent for wastewater treatment purposes.

The oxidation reactions of organic functional groups are one of the important processes in synthesis and chemical industries and have wide applications. Therefore, it is very important to use suitable, cheap, biocompatible, non-toxic catalysts as well as oxidants that do not produce by-products or non-toxic by-products. In the upcoming project, we are trying to use deep eutectic solvents (DESs) containing tempo unit as an active oxidizing catalyst in alcohol oxidation. Numerous catalytic systems have been developed for the aerobic oxidation of alcohols, with TEMPO-based systems utilizing metal co-catalysts being the most extensively studied. This study introduces a novel catalytic system, namely a TEMPO-supported DES (TEMPO-DES) and Fe(NO 3 ) 3 ·9H 2 O for the oxidation of alcohols using molecular oxygen as the terminal oxidant. The TEMPO-DES was prepared by combining salt ([Quaternium-TEMPO] + Cl − ) with glycine. The TEMPO-DES/Fe(NO 3 ) 3 system demonstrated excellent performance in selectively oxidizing various alcohols to their corresponding aldehydes and ketones under mild and solvent-free conditions. Furthermore, the DES could be easily recovered without experiencing significant loss of catalytic activity.

The electrochemical reduction of toxic nitrate wastewater to green fuel ammonia under mild conditions has become a goal that researchers have relentlessly pursued. Existing designed electrocatalysts can effectively promote the nitrate reduction reaction (NO3RR), but the study of the catalytic mechanism is not extensive enough, resulting in no breakthroughs in performance. In this study, a novel mechanism of hydrogenation-facilitated spontaneous N-O cleavage was explored based on density functional theory calculations. Furthermore, the Ead−*OH (adsorption energy of the adsorbed *OH) was used as a key descriptor for predicting the occurrence of spontaneous N-O bond cleavage. We found that Ead−*OH < −0.20 eV results into spontaneous N-O bond cleavage. However, excessively strong adsorption of OH* hinders the formation of water. To address this challenge, we designed the eligible Fe2B2 MBene, which shows excellent catalytic activity with an ultra-low limiting potential for NO3RR of −0.22  V under this novel reaction mechanism. Additionally, electron-deficient Fe active sites could inhibit competing hydrogen evolution reactions (HERs), which provides high selectivity. This work may offer valuable insights for the rational design of advanced electrocatalysts with enhanced performance.

The insight of the activity phase and reaction mechanism is vital for developing high-performance ammonia synthesis electrocatalysts. In this study, the origin of the electronic-dependent activity for the model Cu2O catalyst toward ammonia electrosynthesis with nitrate was probed. The modulation of the electronic state and oxygen vacancy content of Cu2O was realized by doping with halogen elements (Cl, Br, I). The electrocatalytic experiments showed that the activity of the ammonia production depends strongly on the electronic states in Cu2O. With increased electronic state defects in Cu2O, the ammonia synthesis performance increased first and then decreased. The Cu2O/Br with electronic defects in the middle showed the highest ammonia yield of 11.4 g h−1 g−1 at −1.0 V (vs. RHE), indicating that the pattern of change in optimal ammonia activity is consistent with the phenomenon of volcano curves in reaction chemistry. This work highlights a promising route for designing NO3−RR to NH3 catalysts.

Environmental pollution in stream networks is a major concern. In this study, the effects of land-use and geological characteristics on basin-scale sulfate and nitrate dynamics in the Chikusa River basin, Hyogo, Japan, where substantial environmental pollution has not yet been officially reported, were evaluated from the perspective of an overview. Using sulfate and nitrate concentrations as well as their isotopic signatures ( δ 15 N-NO 3 − , δ 18 O-NO 3 − , δ 34 S-SO 4 2− , δ 18 O-SO 4 2− values) as response variables, we employed generalized linear mixed-effects models (GLMMs) to clarify the effects of land coverage, geological rock type, and season on the loading of these solutes. The results obtained showed an increase in sulfate concentration with an increase in the proportional area of exploited land regardless of the season. Isotopic signatures ( δ 34 S-SO 4 2− , δ 18 O-SO 4 2− values) and the GLMMs suggested that sulfate primarily originated from the soil owing to rock weathering processes, and its distribution was mainly driven by the confluence of river branches along with altitude. In contrast, nitrate concentration varied with season, decreasing with an increase in the proportional area of exploited land in summer and showing an opposite trend in winter. The δ 15 N vs. δ 18 O plot showed that the impacts of direct nitrate input from precipitation and chemical fertilizer were negligible, while topically applied manure and septic waste played important roles. The GLMMs also indicated that the proportion of fertilized area affects the spatial distribution of δ 15 N-NO 3 − values but not nitrate concentration, implying the existence of nitrate loading from fertilized areas that could not be detected via concentration-only measurements. Therefore, the combined use of isotopic signatures and GLMMs is expected to provide valuable information for discerning potential sources of pollution in areas without substantial environmental issues. Taken together, this approach could be applied as a “proactive indicator” particularly for areas without apparent pollution, to ensure effective river management.

Ammonium sensitivity is considered a globally stressful condition that affects overall crop productivity. The major toxic symptom associated with ammonium nutrition is growth retardation, which has been associated with a high energy cost for maintaining ion, pH, and hormone homeostasis and, eventually, the NH3/NH4+ level in plant tissues. While certain species/genotypes exhibit extreme sensitivity to ammonium, other species/genotypes prefer ammonium to nitrate as a form of nitrogen. Some of the key tolerance mechanisms used by the plant to deal with NH4+ toxicity include an enhanced activity of an alternative oxidase pathway in mitochondria, greater NH4+ assimilation plus the retention of the minimum level of NH4+ in leaves, and/or poor response to extrinsic acidification or pH drop. Except for toxicity, ammonium can be considered as an energy-efficient nutrition in comparison to nitrate since it is already in a reduced form for use in amino acid metabolism. Through effective manipulation of the NH4+/NO3 − ratio, ammonium nutrition can be used to increase productivity, quality, and resistance to various biotic and abiotic stresses of crops. This review highlights recent advancements in ammonium toxicity and tolerance mechanisms, possible strategies to improve ammonium tolerance, and omics-based understanding of nitrogen use efficiency (NUE) in plants.

Focusing on the ChemFET (chemical field-effect transistor) technology, the development of a multi-microsensor platform for soil analysis is described in this work. Thus, different FET-based microdevices (i.e., pH-ChemFET pNH4-ISFET and pNO3-ISFET sensors) were realized with the aim of monitoring nitrogen-based ionic species in soil, evidencing quasi-Nernstian detection properties (>50 mV/decade) in appropriate concentration ranges for agricultural applications. Using a specific test bench adapted to important earth samples (mass: ~50 kg), first experiments were done in a lab, mimicking rainy periods as well as nitrogen-based fertilizer inputs. By monitoring pH, pNH4, and pNO3 in an acidic (pH ≈ 4.7) clay-silt soil matrix, different processes associated to the nitrogen cycle were characterized over a fortnight, demonstrating comprehensive results for ammonium nitrate NH4NO3 inputs at different concentrations, water additions, nitrification phenomena, and ammonium NH4+ ion trapping. Even if the ChemFET-based measurement system should be improved according to the soil(electrolyte)/sensor contact, such realizations and results show the ChemFET technology potentials for long-term analysis in soil, paving the way for future “in situ” approaches in the frame of modern farming.