NH4NO3 Solution Research Articles

An experimental assessment of fracture parameters and microstructure of concrete exposed to calcium leaching

This study delves into the intricate dynamics of calcium leaching in concrete, employing a comprehensive approach to evaluate its impact on structural durability. Accelerated calcium leaching tests, conducted in NH4NO3 solution with a constant pH under controlled conditions, simulate real-world scenarios. Using methods based on degraded thickness and calcium ion concentration, the study determines the acceleration factor, revealing the material's susceptibility to leaching. The chemical composition of the concrete is analyzed using SEM-EDX and XRD patterns with an energy spectrometer. A detailed examination of 145 concrete beams through Three-Point Bending tests over 150 days demonstrates a proportional decline in fracture toughness and tensile strength by 46.6 % and 44.2 %, respectively. A significant correlation emerges between calcium leaching and the reduction in fracture energy, with a 57.5 % decrease observed after 150 days, while compressive strength decreases by up to 38.57 %. This study introduces novel formulations for fracture parameters of leached concrete by employing the boundary effect method (BEM) to connect with concrete microstructure. This represents a pioneering advancement in fracture mechanics and provides a fresh perspective on understanding and addressing the structural effects of calcium leaching in concrete structures.

Changes in the structure of alkali activated slag mortars subjected to accelerated leaching

The chemically induced degradation of alkali-activated materials exposed to the surrounding environment is a critical concern for durability. In this study, the leaching of alkali activated slag mortars (AASs) subjected to a 6M NH4NO3 solution was investigated by integrating techniques including ICP-OES, XRD/QXRD, TGA/DSC, ATR-FTIR, and 29Si MAS-NMR. The results revealed that the main leachable elements from the AASs and their leaching rates decreased in the following order: Na, K, Ca, and Mg. In contrast, Si and Al, the key elements in the C-A-S-H gel, displayed a remarkable resistance to leaching. Upon NH4NO3 attack, the primary phase (C-A-S-H) becomes more siliceous and has a greater mean chain length through decalcification and dealumination. The second phase, Mg, Al-layered double hydroxide (Mg, Al-LDH, or hydrotalcite), incorporated nitrate from the surrounding solution, sulfate from precursor dissolution, and Ca from gel decalcification to form nitrate/sulfate-bearing Ca, Al-LDH phases. Remarkably, the water-to-binder ratio exerted a nuanced influence, dictating the pace of element leaching, while exhibiting a relatively modest impact on the stability of the solid phases after 28 days of exposure. This work proposes a leaching mechanism for understanding the leaching process occurring in AASs based on an in-depth experimental exploration of mineralogical alterations.

Nitrogen fertilization practices alter microbial communities driven by clonal integration in Moso bamboo

Nitrogen (N) fertilization is crucial for maintaining plant productivity. Clonal plants can share resources between connected ramets through clonal integration influencing microbial communities and regulating soil biogeochemical cycling, especially in the rhizosphere. However, the effect of various N fertilization practices on microbial communities in the rhizosphere of clonal ramets remain unknown. In this study, clonal fragments of Moso bamboo (Phyllostachys edulis), consisting of a parent ramet, an offspring ramet, and an interconnecting rhizome, were established in the field. NH4NO3 solution was applied to the parent, offspring ramets or rhizomes to investigate the effect of fertilization practices on the structure and function of rhizosphere microbial communities. The differences in N availability, microbial biomass and community composition, and abundance of nitrifying genes among rhizosphere soils of ramets gradually decreased during the rapid growth of Moso bamboo, irrespective of fertilization practice. The soil N availability variation, particularly in NO3−, caused by fertilization practices altered the rhizosphere microbial community. Soil N availability and stable microbial biomass N in parent fertilization were the highest, being 9.0 % and 18.7 %, as well as 60.8 % and 90.4 % higher than rhizome and offspring fertilizations, respectively. The microbial network nodes and links in rhizome fertilization were 1.8 and 7.5 times higher than in parent and offspring fertilization, respectively. However, the diversity of bacterial community and abundance of nitrifying and denitrifying genes were the highest in offspring fertilization among three practices, which may be associated with increased N loss. Collectively, the rhizosphere microbial community characteristics depended on fertilization practices by altering the clonal integration of N in Moso bamboo. Parent and rhizome fertilization were favorable for N retention in plant-soil system and resulted in more stable microbial functions than offspring fertilization. Our findings provide new insights into precision fertilization for the sustainable Moso bamboo forest management.

Mathematical Modeling of Absorption-adsorption Processes for Waste Free Decontamination of Gases from SO2 in a Bubble Tray Column

Mathematical Modeling of Absorption-adsorption Processes for Waste Free Decontamination of Gases from SO₂ in a Bubble Tray Column

Eco-friendly technology for “Nitrofos” fertilizer obtained from radioactive man-made waste

The article presents the results of research into the process of purification of phosphoric acid from radioactive isotopes after extraction of uranium, thorium, and REE. It is shown that the main purification of acid is achieved in the process of gypsum precipitation with sulfuric acid and barium nitrate. Additional purification of nitrate-phosphate solution is achieved after uranium extraction and sorption-extraction purification of REE. The sorption raffinate with a concentration of P2O5 25 g/L, REE 0.5 g/L and NH4NO3 300 g/L were used for fertilizer production. Additional purification of NH4NO3 solution from isotopes 226Ra, 210Po, 227Ac is achieved in the process of REE extraction purification. The aggregate of all refining processes of purification of nitrate-phosphate solution from radioactive isotopes provided NP-fertilizer “Nitrofos”, which meets the quality standards. Extraction of P2O5 from raw materials into NP-fertilizer – 90%; extraction of REE from raw materials into collective chemical concentrate – 95%; direct commercial extraction of REE from raw materials into the product – 85%.

Interaction of sodalite and cancrinite with NH4NO3 solution. First case of low-temperature synthesis of buddingtonite

Hydroxyl sodalite and sulfate cancrinite were synthesized from fly ash from TPP Varna, Bulgaria. The interaction of the two feldspathoids with NH4NO3 solution at 90 °C was investigated. Because of the reaction, sodalite is dissolved and ammonium feldspar (buddingtonite) is formed, which is the first case of low-temperature synthesis of this mineral. The interaction of cancrinite with NH4NO3 induces ion exchange and the formation of cancrinite with composition (NH4)5.4Na3.6(NO3)1.45(SO4)0.25(OH)0.05[Al6Si6O24]·2H2O, suggesting potential for the use of this form as a slow-acting fertilizer.

Growth of large norsethite crystals in aqueous ammonium nitrate solutions

Crystallization of norsethite [BaMg(CO3)2] receives considerable attention as a key for solving geological problems, and environmental and resource issues. Noresthite is poorly soluble in water, and is synthesized via witherite [BaCO3] by solution-mediated transformation. In contrast, owing to the difficulties such as tremendous growth time and consideration of multi-step reactions, the shape and size of norsethite were not satisfactory for further investigations so far. Here we tried to increase the solubility of the crystals to overcome these difficulties of the growth by adding NH4NO3. The solubilities of norsethite and witherite in the presence of NH4NO3 were ∼35 and ∼45 times higher than those in the absence of NH4NO3, respectively. At 90 °C, the growth rate of norsethite in NH4NO3 solutions was ∼17 times higher than that in NH4NO3-free solutions, and norsethite in NH4NO3 solutions nucleated immediately after mixing the raw materials. Finally, we succeeded in synthesizing bulky norsethite crystals of 170 μm size only in one month, utilizing 0.1–1 M NH4NO3 solutions of 90 °C. We could explain the appearance of large norsethite, considering that norsethite dominantly consumes the solute by adding NH4NO3 compared with witherite. The findings provide a breakthrough in the growth technique of double carbonates.

Introduction of Heavy Micro‐Titanium‐Carbide Particles into Zn–Ni Coatings on Steel During In Situ Brush Electroplating

The heavy micro‐titanium‐carbide (TiC) particles are first introduced into brush‐electroplated Zn–Ni coating (TiC‐0 coating) by using some surfactants here. The effect of TiC concentration of brush‐electroplating solution on the properties of Zn–Ni–TiC coatings is investigated. It is found that the coating hardness and corrosion resistance are enhanced significantly due to the co‐deposition of TiC and an optimal coating with a thickness of 71 μm and adhesive strength of 37.2 MPa is obtained when TiC concentration was 40 (g L−1) (TiC‐40 coating). The pencil hardness of TiC‐0 and TiC‐40 is 2 H and 5 H, respectively. The corrosion resistance time to hot NH4NO3 solution (or inferred neutral salt spray) of TiC‐0 and TiC‐40 are 40 and 240 min (or 321 and 1995 h), respectively. Many pores appear on the coating due to the incomplete overlap of many batch layers. The TiC content is the factor dominating the coating hardness and corrosion resistance by changing the structure, contact angle, and pore diameter of coating, thereby changing the linear polar resistance Rp from potentiodynamic polarization curves, charge‐transfer resistance Rct or |Z|0.01 Hz, or polarization resistance from electrochemical impedance spectroscopy. The content of Zn–Ni alloy is the factor dominating the adhesive strength of Zn–Ni–TiC coating.

High-performance rare-earth hard magnetic nanoparticles via the calciothermic reduction and chemoselective dissolution

Magnetic Nd2Fe14B nanoparticles are synthesized by a bottom-up process via calciothermic reduction, which complements the negative reduction potential of rare-earth elements, thus affording nanoscale products. However, to obtain high-purity, high-performance magnetic nanoparticles, residual calcium by-products that persist after calcium thermal reduction-diffusion must be selectively removed. In previously reported rinsing methods, H2O or H+ diffuse into the magnetic nanoparticles, thereby leading to hydridation. Herein, we propose a novel rinsing solution, NH4NO3/methanol, that does not deteriorate the magnetic properties. The magnetic properties are enhanced by selectively removing calcium by-products (i.e., CaO) from the magnetic nanoparticles with NH4NO3/methanol solution and by preventing hydridation and oxidation using zeolite and Schlenk line. The intrinsic coercivity (Hci) is maintained at 75.1 % (from 8.5 kOe to 6.3 kOe), and the saturation magnetization (Ms) increases two-fold (110.08 emu/g) after rinsing with NH4NO3 solution, compared with prior to rinsing treatment (47.363 emu/g). Rinsing the magnetic nanoparticles with NH4NO3/methanol solutions does not cause deterioration of the obtained Nd2Fe14B nanostructures, where Ms = 112.0 emu/g and Hci = 8.4 kOe after rinsing with NH4NO3/methanol using the zeolite and Schlenk line. Using rinsing methods in previous studies. 3.5 % of the initial coercivity is maintained, whereas with the new rinsing method, 95.2 % of the coercivity is maintained, thus indicating that rinsing does not induce deterioration of the magnetic properties.

The halopriming of seeds improves the germination, growth, physiological and phytochemical attributes of tomato under saline conditions

The low seed germination response and seedling growth of crops to salinity is common problem in Pakistan. To overcome this problem,seed priming is used as an economic and effective approach. Present study was conducted to evaluate the effects of halopriming ofseeds on germination, growth and yield of tomato under saline conditions. The seeds of tomato variety ‘Raja’ were primed with 0, 50mM and 100mM of NH4NO3, KNO3, and (NH4)2SO4 solutions for 12 and 24 hours. The primed seeds were irrigated separately with tapwater, saline water, and Hoagland solution with saline water. The results indicated that halopriming of tomato seeds with KNO3, NH4NO3and (NH4)2SO4 significantly increased the germination percentage (GP) from 58% (unprimed) to 95% (primed) while decreased the meangermination time (MGT) from 7.44 days (unprimed) to 4.6 days (primed). A significant increase was observed in the height of plant, leafarea, number of leaves, shoot and root biomass, number of fruits per plant, etc. in primed plants irrigated with Hoagland solution undersaline conditions. Similarly, the halopriming with NH4NO3 and KNO3 also enhanced the chlorophyll pigments, lycopene contents, totalsoluble sugars, total proteins, total phenolic contents and total flavonoids in primed plants irrigated with Hoagland solutions under saltstress. Furthermore, proline contents were increased in primed plants irrigated with NaCl solution as compared to other treatments andcontrol. In conclusion, KNO3 and NH4NO3 are more effective priming agents than (NH4)2SO4 were positively affected the germination, plantheight, physiological and biochemical attributes in tomato plants under saline and non-saline conditions. The supplement of Hoaglandsolution under salt stress further improves the morphological, physiological and biochemical attributes of tomato.

Soil CO2 and N2O emissions and microbial abundances altered by temperature rise and nitrogen addition in active-layer soils of permafrost peatland.

Changes in soil CO2 and N2O emissions due to climate change and nitrogen input will result in increased levels of atmospheric CO2 and N2O, thereby feeding back into Earth's climate. Understanding the responses of soil carbon and nitrogen emissions mediated by microbe from permafrost peatland to temperature rising is important for modeling the regional carbon and nitrogen balance. This study conducted a laboratory incubation experiment at 15 and 20°C to observe the impact of increasing temperature on soil CO2 and N2O emissions and soil microbial abundances in permafrost peatland. An NH4NO3 solution was added to soil at a concentration of 50 mg N kg-1 to investigate the effect of nitrogen addition. The results indicated that elevated temperature, available nitrogen, and their combined effects significantly increased CO2 and N2O emissions in permafrost peatland. However, the temperature sensitivities of soil CO2 and N2O emissions were not affected by nitrogen addition. Warming significantly increased the abundances of methanogens, methanotrophs, and nirK-type denitrifiers, and the contents of soil dissolved organic carbon (DOC) and ammonia nitrogen, whereas nirS-type denitrifiers, β-1,4-glucosidase (βG), cellobiohydrolase (CBH), and acid phosphatase (AP) activities significantly decreased. Nitrogen addition significantly increased soil nirS-type denitrifiers abundances, β-1,4-N- acetylglucosaminidase (NAG) activities, and ammonia nitrogen and nitrate nitrogen contents, but significantly reduced bacterial, methanogen abundances, CBH, and AP activities. A rising temperature and nitrogen addition had synergistic effects on soil fungal and methanotroph abundances, NAG activities, and DOC and DON contents. Soil CO2 emissions showed a significantly positive correlation with soil fungal abundances, NAG activities, and ammonia nitrogen and nitrate nitrogen contents. Soil N2O emissions showed positive correlations with soil fungal, methanotroph, and nirK-type denitrifiers abundances, and DOC, ammonia nitrogen, and nitrate contents. These results demonstrate the importance of soil microbes, labile carbon, and nitrogen for regulating soil carbon and nitrogen emissions. The results of this study can assist simulating the effects of global climate change on carbon and nitrogen cycling in permafrost peatlands.

Mineralogical and microstructural changes in alkali-activated and hybrid materials exposed to accelerated leaching

Alkali-activated materials (AAM) and hybrid cements (HC) have become sustainable alternatives to Portland cement (PC) due to their low carbon footprint. The main differences between AAM and HC lie in their content of clinker (none in the AAM and usually lower than 30% for HCs) and the type of activator used (strong alkaline solutions for AAM and small amounts of solid alkalis for HC). Durability problems related with microstructural changes due to decalcification and leaching of the cementitious paste have been well researched for PC pastes, but it is still not well known for AAM and HC. The present work aims to study the leaching process for cement pastes of both types of sustainable pastes.Blast furnace slag (BFS) was selected as a precursor to manufacture hybrid slag (HS) pastes and alkali-activated slag (AAS) pastes. A commercial CEM IV was selected as reference material. A 6 M NH4NO3 solution was used to accelerate leaching kinetics. After 28 days of immersion, the mineralogical and microstructural changes were evaluated.Results show that AAS pastes exhibited the highest leaching resistance of all the pastes under study, due to the absence of portlandite and the high level of polymerization of silicate chains. In HS pastes, the presence of portlandite (due to PC in the material) and gypsum (due to the activator) explains their intermediate performance, in between CEM IV and AAS.

Enhanced Isohydric Behavior Decoupled the Whole-Tree Sap Flux Response to Leaf Transpiration under Nitrogen Addition in a Subtropical Forest

Anthropogenic nitrogen deposition has the potential to change the leaf water-use strategy in the subtropical region of China. Nevertheless, the whole-tree level response crucial for the ecosystem functions has not been well addressed over the past decades. In this study, the stem sap flux density (JS) was monitored for the whole-tree water transport capacity in two dominant species (Schima superba and Castanopsis chinensis) in a subtropical forest. To simulate the increased nitrogen deposition, the NH4NO3 solutions were sprayed onto the forest canopy at 25 kg ha−1 year−1 (CAN25) and 50 kg ha−1 year−1 (CAN50), respectively, since April 2013. The JS and microclimate (monitored since January 2014) derived from the whole-tree level stomatal conductance (GS) were used to quantify the stomatal behavior (GS sensitive to vapor pressure deficit, GS-VPD) in response to the added nitrogen. The maximum shoot hydraulic conductance (Kshoot-max) was also measured for both species. After one-year of monitoring in January 2015, the mid-day (JS-mid) and daily mean (JS-mean) sap flux rates did not change under all the nitrogen addition treatments (p > 0.05). A consistent decline in the GS-VPD indicated an enhanced isohydric behavior for both species. In addition, the GS-VPD in the wet season was much lower than that in the dry season. S. superba had a lower GS-VPD and decreased JS-mid/JS-mean, implying a stronger stomatal control under the fertilization, which might be attributed to the low efficient diffuse-porous conduits and a higher JS. In addition, the GS for S. superba decreased and the GS-VPD increased more under CAN50 than that under CAN25, indicating that the high nitrogen dose restrains the extra nitrogen benefits. Our results indicated that the JS for both species was decoupled from the leaf transpiration for both species due to an enhanced isohydric behavior, and a xylem anatomy difference and fertilization dose would affect the extent of this decoupling relation.

Nitrogen addition may promote soil organic carbon storage and CO2 emission but reduce dissolved organic carbon in Zoige peatland

With the increase of nitrogen (N) deposition, N input can affect soil C cycling since microbes may trigger a series of activities to balance the supply and demand of nutrients. However, as one of the largest C sinks on earth, the role of extra N addition in affecting peatland soil C and its potential mechanism remains unclear and debated. Therefore, this study chose the largest peatland in China (i.e., Zoige, mostly N-limited) to systematically explore the potential changes of soil C, microbes, and ecoenzymes caused by extra N input at the lab scale incubation. Three different types of soils were collected and incubated with different levels of NH4NO3 solution for 45 days. After incubation, N input generally increased soil organic C (SOC) but decreased dissolved organic carbon (DOC) in Zoige peatland soils. Moreover, CO2 and CH4 emissions were significantly increased after high N input (equal to 5 mg NH4NO3 g−1 dry soils). Through a series of analyses, it was observed that microbial communities and ecoenzyme activities mainly influenced the changes of different C components. Collectively, this study implied that the increasing N deposition might help C sequestration in N-limited peatland soils; simultaneously, the risk of increased CO2 and CH4 by N input in global warming should not be ignored.

Phase separation and thermodynamics of the mixture of metformin hydrochloride + triton X-100 in ammonium salts media: impacts of composition of media

Cloud point (CP)/lower consolute temperature (LCT) of aqueous mixture of TX-100 and a highly recognised anti-diabetic drug metformin hydrochloride (MNH) was analysed in absence/presence of NH4Cl, NH4NO3, (NH4)2SO4 and (NH4)2HPO4. The CP values were found to be decreased with increasing concentrations of ammonium salts. Occurrence of aggregation in respective solution systems might result in declining of corresponding CP. Thermodynamic parameters (, and ) were calculated at CP. The appearance of positive values of Gibbs free energy () indicates that clouding in the studied system was thermodynamically non-spontaneous and the degree of non-spontaneity was diminished with increasing in the extents of electrolytes. The computed enthalpy () and entropy () values of the system showed negative values in cases of aq. NH4Cl, (NH4)2SO4 and (NH4)2HPO4 while the negative values tend to reduce with rise of electrolytes content. In case of aq. NH4NO3 medium, the reverse results for the and values were detected. The and values in the studied system indicate the presence of electrostatic interaction between TX-100 and MNH in NH4Cl, (NH4)2SO4, (NH4)2HPO4 media whereas the hydrophobic interactivity might play a great role within the mixture when it was placed in the NH4NO3 solution.

Nitrogen Fertilization Increases Soil Microbial Biomass and Alters Microbial Composition Especially Under Low Soil Water Availability.

Soil microbial biomass and composition are affected by resource supply and water availability. However, the response of soil microbial communities to nitrogen fertilization under different water availability conditions is unclear. Therefore, this study conducted a 6-year pot experiment comprising five watering regimes (40%, 50%, 60%, 80%, and 100% of field capacity (FC)) and three nitrogen fertilization levels (NH4NO3 solution; 0 [N0], 20 [N1], and 40 [N2] g N m-2year-1) to investigate soil microbial biomass, composition, and properties. The results indicated that soil microbial biomass and composition were more strongly affected by nitrogen fertilization compared with water regime. Nitrogen fertilization increased soil microbial biomass and altered soil microbial community composition, especially under low soil water availability. Soil microbial biomass was positively linearly associated with soil water regimes under N0, whereas it responded polynomially to soil water regimes under N1 and N2. The maximal soil microbial biomass was observed at FC80 for N1 and FC60 for N2. Furthermore, the biomass of soil microbial groups with high nitrogen and carbon acquisition ability as well as the enzyme activities of carbon and nitrogen cycling (β-1,4-glucosidase and β-1,4-N-acetyl-glucosaminidase, respectively) were stimulated by nitrogen fertilization. Soil microbial biomass was affected directly by nitrogen fertilization and indirectly by nitrogen and water regimes, via altering soil pH, dissolved inorganic nitrogen (NH4+-N and NO3--N) concentration, and soil organic carbon concentration. This study provides new insights into the effect of interaction between soil nitrogen and water availabilities on soil microbial biomass, composition, and its underlying mechanism.

Optimizing NH4+ Storage Capability of Nickel Ferrocyanide by Regulating Coordination Anion in Aqueous Electrolytes

AbstractWill anions in electrolytes affect the electrochemical properties of Prussian blue analogues for aqueous ammonium ion batteries? In this study, the electrochemical reaction between nickel ferrocyanide and ammonium ions is investigated in three common inorganic ammonium salt solutions [NH4NO3, NH4Cl, and (NH4)2SO4]. The results suggest that at the same NH4+ concentration, nickel ferrocyanide exhibits different electrochemical performances. The as‐prepared nickel ferrocyanide contains two phases, which are rhombohedral phase and cubic phase. Rhombohedral phase of nickel ferrocyanide has a high reactivity in 0.5 M (NH4)2SO4 solution during cycling while cubic phase shows good performance in 1 M NH4NO3 and 1 M NH4Cl electrolyte. It should be noted that the performance of cubic phase is superior to rhombohedral phase in kinetic consideration. Additionally, due to the strong coordination ability of chloride, nickel ferrocyanide exhibits an excellent electrochemical performance in 1 M NH4NO3 solution, rather than 1 M NH4Cl electrolyte.

Acid Catalysis over Low-Silica Faujasite Zeolites

Low-silica faujasite (FAU) zeolites (with Si/Al ratio of ca. 1.2-1.8) sustain framework integrity and porosity upon moderate ion exchange (0.01 M NH4NO3 solution for 1 h at ambient temperature), which introduces two kinds of protons, distinctive in reactivity and coordination to the zeolite framework, within supercages (HSUP). Moderate ion exchange limited within supercages transpires while maintaining full occupancy of Na+ cations within associated sodalite cages; this in turn helps stabilize the framework of low-silica H-FAU zeolites. Protons located on site II (H3630) and site III (H3650) within supercages on low-silica FAU zeolites can be classified and enumerated by virtue of infrared spectroscopy, providing an opportunity to compare reactivities of these distinct protons for monomolecular protolytic reactions of propane. Protons on site II exhibit prominently higher reactivity for monomolecular propane dehydrogenation and cracking than protons on site III. Low-silica proton-form FAU zeolites (zeolite X) upon moderate ion exchange possess protons on site III that are unavailable on high-silica FAU zeolites (zeolite Y) and limit ion exchange within supercages, providing unprecedented high-temperature structural and chemical stability (>773 K) and enabling their application as solid-acid catalysts.

Characterization of the bark storage protein gene (JcBSP) family in the perennial woody plant Jatropha curcas and the function of JcBSP1 in Arabidopsis thaliana.

BackgroundBark storage protein (BSP) plays an important role in seasonal nitrogen cycling in perennial deciduous trees. However, there is no report on the function of BSP in the perennial woody oil plant Jatropha curcas.MethodsIn this study, we identified six members of JcBSP gene family in J. curcas genome. The patterns, seasonal changes, and responses to nitrogen treatment in gene expression of JcBSPs were detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Overexpression of JcBSP1 in transgenic Arabidopsis thaliana was driven by a constitutive cauliflower mosaic virus (CaMV) 35S RNA promoter.ResultsJcBSP members were found to be expressed in various tissues, except seeds. The seasonal changes in the total protein concentration and JcBSP1 expression in the stems of J. curcas were positively correlated, as both increased in autumn and winter and decreased in spring and summer. In addition, the JcBSP1 expression in J. curcas seedlings treated with different concentrations of an NH4NO3 solution was positively correlated with the NH4NO3 concentration and application duration. Furthermore, JcBSP1 overexpression in Arabidopsis resulted in a phenotype of enlarged rosette leaves, flowers, and seeds, and significantly increased the seed weight and yield in transgenic plants.

Effects of artificial nitrogen deposition on the forest floor and soil chemistry in chestnut-leaved oak (Quercus castaneifolia) plantation in northern Iran

Human demand for food and energy has led to significant changes in the level of reactive nitrogen (N) released to the atmosphere and then deposited in the biosphere. This study aimed to investigate the impact of the deposition of artificial N on the forest floor and on the soil chemical properties in an oak (Quercus castaneifolia C.A. Mey.) plantation in northern Iran. Twelve plots of 200 m2 (20 m × 10 m) were set up in the study area. Four N treatments were considered: zero (control), 50 (low), 100 (medium), and 150 (high) kg N·ha−1·year−1. N in the form of NH4NO3 solution was manually sprayed onto the understory plots monthly for 1 year. The total N, phosphorus (P), potassium (K), and organic carbon (OC) of the forest floor were measured. Soil N, available P, available K, pH, EC (electrical conductivity), OC, microbial biomass C (MBC), and urease enzyme activity were measured in the 0–10 cm depth. The concentration of total N and P of the forest floor was significantly higher in the high-N treatment. The total concentration of N (+36%), the urease activity (+44%), and EC (+12%) of soil increased with raising the high-N treatment compared to the control, but the MBC (−20%), available P (−28%), and available K (−15%) were significantly reduced in the high-N treatment. Our results were obtained with simulated deposition rates that exceed ambient fluxes, but ambient N deposition is nevertheless high in our study area.