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Highlights • Fertigation with treated wastewater can supplement N and P fertilisers in peri-urban agriculture. • Fertigation with treated wastewater increases soil inorganic N and P which may be taken up by plants or leached. • Irrigation scheduling reduces the risks of N and P leaching down the soil profile to groundwater resources. • Sustainable fertigation using DEWATS effluent needs monitoring for pathogens and trace elements accumulation. Abstract Municipalities in South Africa face problems in providing sanitation to unserved informal settlements in peri-urban areas and rural nodes. The Decentralised Wastewater Treatment System (DEWATS) connected to community ablution blocks can be an option, with the treated effluent then applied to agricultural land. However, the management of treated wastewater through irrigation of crops must be environmentally sustainable. This study therefore investigated nitrogen (N) and phosphorus (P) dynamics in soil irrigated with DEWATS effluent. A field study with banana and taro in a randomised complete block design with three blocks and two irrigation treatments (DEWATS effluent without fertiliser vs tap water + fertiliser) was carried out over a period of 992 days at the Newlands-Mashu Research Site, Durban, South Africa. Data were collected on crop N and P uptake, soil chemical properties, and nutrient leaching together with groundwater monitoring. Nitrogen and P uptake was not significantly different (p > 0.05) between the two irrigation treatments. Irrigation with DEWATS effluent increased soil N and P concentrations within the upper 0.3 m implying its importance as a fertiliser source. Leaching of N and P from DEWATS effluent treated plots was comparable to that from the tap water + fertiliser treatments. However, to manage excess water in the soil, practices such as irrigation to meet crop water requirements with room for rainfall and installation of subsurface drainage when possible can be employed. [ABSTRACT FROM AUTHOR]

A urease extract prepared by decanting liquid from a suspension of finely ground Citrullus lanatus (watermelon) seeds was characterized and applied to dilute urine samples to demonstrate a low-cost field method to estimate total Kjeldahl nitrogen (TKN) concentrations in human urine. The extract exhibited a Michaelis-Menten constant, Km, of 3.00 mM urea and a specific activity of up to 12.2 U/mg protein at an optimum pH of 8.1. A statistical F-test on 54 samples demonstrated that TKN can be estimated as the total ammonium-nitrogen recovered upon addition of urease in dilute fresh and stale urine samples. The total ammonium-nitrogen in urine samples determined after treatment with watermelon seed urease was consistent with that determined using traditional acid digestion techniques. The extract retained 85% of its initial capacity after three months of refrigeration. The effectiveness of this method to assay nitrogen in unbuffered urine samples will be useful in nitrogen analyses in nutrient recovery and urine or slurry storage contexts. Accordingly, this study is useful in understanding the kinetics of a plant-derived urease acting in dilute urine. [ABSTRACT FROM AUTHOR]

Two ternary nitride perovskites Co3InN and Ni3InN have been synthesized electrochemically at 723 K in a molten salt LiCl/KCl:Li3N. The working electrode, which was either a pre‐molten alloy of Co/In or Ni/In, was anodically polarized at 2.6 V during synthesis. Lattice parameters refined by the Rietveld method are a = 385.180(8) pm for Co3InN and a = 385.99(1) pm for Ni3InN. EDX measurements confirm the atomic ratios of 3:1 of the metallic elements. Chemical analyses on nitrogen content result in compositions of Co3InN1.13 and Ni3InN0.95, respectively. Furthermore, particle size of Co3InN is 1–3 µm and of Ni3InN 5–20 µm. Co3InN shows spin‐glass behavior with a freezing temperature of about 11 K at 100 Oe. For the first time, ternary nitrides were electrochemically synthesized from a molten salt melt, namely the two cubic perovskites Co3InN and Ni3InN. A small addition of lithium nitride provides an initial nitrogen reservoir during synthesis, while nitrogen supply is managed via a nitrogen electrode. Co3InN shows spin‐glass behavior with a freezing temperature of about 11 K at 100 Oe. [ABSTRACT FROM AUTHOR]

Abstract To maintain the pressure of cargo tank and to minimize natural gas loss, two nitrogen expansion cycles for boil-off gas (BOG) re-liquefaction systems, specifically designed for small LNG ships are proposed and optimized: 1) Case 1, re-liquefaction process with the parallel nitrogen expansion, 2) Case 2, re-liquefaction process with the serial nitrogen expansion. The simulation and analysis of the two processes are carried out by using Aspen HYSYS and the genetic algorithms are selected as the optimization method. It can be found that the specific energy consumption (SEC) of 0.7333 kWh/kg LNG , the coefficient of performance (COP) of 0.2538 and the figure of merit (FOM) of 0.2827 are achieved in Case 1 and the SEC of 0.7539 kWh/kg LNG , the COP of 0.2464 and the FOM of 0.2757 are achieved in Case 2 by comparing the two optimized cases. Moreover, the total exergy losses for Case 1 and Case 2 are 153.34 kW and 160.69 kW, respectively. Highlights • Two BOG re-liquefaction systems designed for small LNG ships are proposed. • Genetic algorithm is selected as the optimization method for the two processes. • The SEC, COP and FOM of the two proposed systems are compared and analyzed. • The proposed systems and other systems are compared and analyzed. [ABSTRACT FROM AUTHOR]

The Galápagos Penguin Spheniscus mendiculus, Flightless Cormorant Phalacrocorax harrisi, and Waved Albatross Phoebastria irrorata are endemic to Islas Galápagos. They are known to feed on different prey (including crustaceans, cephalopods, and/or several species of epipelagic and benthic fish), in accordance with different foraging strategies. In this work, we used stable-isotope analysis of carbon and nitrogen to corroborate available information on habitat use (δ13C) and trophic position (δ15N). Feather samples from the three species were collected in six different areas prior to the 2011 and 2012 breeding seasons. Results showed differences in foraging strategies between Galápagos Penguins and the other two species (δ13C and δ15N, P < 0.01). The Flightless Cormorant and Waved Albatross showed similar proportions of δ13C (P = 0.07), but they occupied different trophic levels (δ15N, P < 0.01). Isotopic signatures in Galápagos Penguins reflected differences based on their breeding areas (δ13C and δ15N, P < 0.01), which were subject to different environmental conditions. This information could be used to evaluate future ecological conditions among the feeding areas of these species. [ABSTRACT FROM AUTHOR]

Abstract The microstructural evolution, strength, ductility change, and precipitates in the base metal and coarse-grain heat-affected zone (CGHAZ) of high nitrogen austenitic stainless steel with different thermal cycles were investigated. The research results indicate that the grain size of austenite and the precipitates reduced while the strength improved with increasing cooling rate. Furthermore, the shape and formation location of the precipitates that were proved to be M 23 C 6 and Cr 2 N by transmission electron microscopy (TEM) varied with the cooling rate. M 23 C 6 precipitated from the catenary to the round type and from the grain boundary to the grain interior with increasing cooling rate, causing the transformation of the fracture mode from an intergranular fracture to a transcrystalline fracture. Cr 2 N precipitated cellularly and was detrimental to the mechanical properties. The low cooling rate (<5 °C/s) deteriorated the strength and ductility owing to the mass of intermetallic compounds, while the properties of the simulated specimens above 5 °C/s were better than those of the base metal. However, the ductility was the best at 5 °C/s and the fracture surface consisted of many deep dimples. Meanwhile, the grains deformed and increased as the cooling rate changed from 1 °C/s to 30 °C/s according to electron backscatter diffraction (EBSD). Further, the results of Taylor factor are consistent with the variation in ductility. Highlights • The improved strengths are obtained with the increase of cooling rate. • Change of precipitates with cooling rate is quantitatively analyzed. • The mode between microstructure and mechanical property is established. • The fracture behavior and strengthening mechanism are studied. • Taylor factor can predict the change of the elongation and explained ductility change. [ABSTRACT FROM AUTHOR]

Abstract Monolithic, nitrogen-doped carbon sorbents were prepared from resorcinol-urea-formaldehyde resins and physically activated with CO 2 for different activation times. The effect of the activation time on the water sorption behavior and the physicochemical properties were investigated. Longer activation times lead to a steeper slope of the water sorption isotherm and, due to a higher specific surface area and micropore volume, an increased water sorption capacity. It was found that, after physical activation for 3 h at 800 °C, the physically activated, nitrogen-doped carbon has a high surface area (>1000 m2/g) and a high water sorption capacity (50 wt%). In a miniaturized adsorption heat pump test stand, the best candidate material was assessed alongside commercial silica gel for reference. At a temperature swing from 90 °C → 50 °C, the CO 2 -activated carbon exhibits a maximal specific cooling power which is a factor of 1.7 higher in comparison with the reference silica gel (429 W/kg versus 255 W/kg). At a more applicable temperature swing, 60 °C → 30 °C, the CO 2 -activated carbon yields a specific cooling power 3.8 times higher than that of the silica gel reference (932 W/kg versus 240 W/kg). Graphical abstract Image 1 Highlights • Nitrogen-doped carbons were pyrolyzed in nitrogen and activated in carbon dioxide. • Longer activation times lead to a higher surface area and water sorption capacity. • Adsorbents were tested in a miniaturized adsorption heat pump test stand. • At a temperature swing, 60 °C.→ 30 °C, the carbon outperforms silica gel by a factor of 3.8 [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Thousand-kernel weight increased with late harvest, increasing grain yield of summer maize. • Late harvest promoted N accumulation after tasseling and N translocation to grain. • N accumulation played a crucial role in the early and middle period, and N translocation did in the mid-late period. Abstract The farmers are accustomed to harvesting summer maize around September 20, but the maize has not yet reached physiological maturity in the Huang-Huai-Hai region, which is adverse for grain yield and mechanized harvest. In order to explore the effect of harvest date on grain yield and nitrogen utilization of summer maize, two treatment in 2016 (CK and 10d) and four treatments in 2017 (CK, 3d, 6d, 10d) were conducted. The sowing dates of all treatments were June 13, and the harvest dates of CK, 3d, 6d and 10d were September 20, 23, 26 and 30, respectively. We found that grain yield and thousand-kernel weight of 10d significantly increased by 17.4–19.8% and 16.8–19.6%, respectively, compared to CK. And partial factor productivity of nitrogen of 10d was 17.4–19.7% higher than that of CK. The grain nitrogen concentration of 3d, 6d and 10d increased by 5.4%, 9.0%, and 9.3–10.8% compared to CK, which promoted nitrogen harvest index, physiological nitrogen use efficiency and partial factor productivity of nitrogen. The reason why nitrogen utilization efficiency increased was that late harvest promoted nitrogen accumulation after tasseling and nitrogen translocation to grain. The nitrogen translocation of 6d was 10.0% in 2017 higher, and that of 10d was 25.1% in 2016 and 15.3% in 2017 higher, respectively, compared to CK. The nitrogen accumulation of 10d increased by 39.0% in 2016, and that of 3d, 6d and 10d increased by 46.5%, 51.3% and 57.3% in 2017, compared to CK. In conclusion, the thousand-kernel weight increased with the delay of harvest date, resulting in increases in grain yield of summer maize. The late harvest promoted nitrogen utilization efficiency resulting from higher nitrogen accumulation after tasseling and higher nitrogen translocation to grain. The contribution of nitrogen translocation to grain yield appeared in the mid-late period (September 23–30), while the contribution of nitrogen accumulation after tasseling did in the early and middle period (September 20–26). Considering annual production of winter wheat-summer maize, the optimized harvest date for summer maize is 6–10 days later than the conventional pattern in this study, that is the cumulative growing degree-days after tasseling reach 613.2–711.5 °C at least. [ABSTRACT FROM AUTHOR]

The goat's rue rhizobia (Neorhizobium galegae) represent a convenient model to study the evolution and speciation of symbiotic bacteria. This rhizobial species is composed of two biovars (bv. orientalis and bv. officinalis), which form N2-fixing nodules with certain species of goat's rue (Galega orientalis and G. officinalis). The cross-inoculation between them results in the formation of nodules unable to fix nitrogen. On the basis of the data on the whole-genome sequencing, we studied the nucleotide polymorphism of 11 N. galegae strains isolated from the North Caucasus ecosystems, where G. orientalis has higher diversity than G. officinalis. The low level of differences in the polymorphism within the group of the sym genes in comparison with the nonsymbiotic genes can be associated with the active participation of host plants in the evolution of rhizobia. The intragenic polymorphism of bv. orientalis proved to be significantly higher than that of bv. officinalis. The level of polymorphism of nonsymbiotic genes was lower than that of the symbiotic genes, which are functionally more homogeneous. The divergence of the nitrogen fixation genes (nif/fix) is more pronounced than that of the nodule formation genes (nod) in the N. galegae biovars. These facts indicate the leading role of the host-specific nitrogen fixation in the evolution of the studied rizhobial species. [ABSTRACT FROM AUTHOR]

Carbon‐and‐oxygen‐doped AlN specimens were prepared by combustion synthesis using Al, graphite, and AlN. Graphite addition changed the product color from white to blue. By XRD, the lattice constant increased slightly with increasing carbon content. Blue AlN powder was synthesized with a molar ratio of the diluent AlN of 0.2‐0.5 with a fixed graphite content of 0.05. At an AlN molar ratio exceeding 0.6, carbon was not successfully incorporated due to the lower reaction temperature. Calcination at 800°C in air removed residual graphite without changing the crystal structure or product color. Oxygen, nitrogen, and carbon analyses revealed that blue AlN powders contained 0.45‐0.54 mass% carbon and 1.4‐1.6 mass% oxygen, while the undoped AlN contained 0.021 mass% carbon and 0.94 mass% oxygen. The origin of the white‐to‐blue color change was investigated via reflection measurements. Blue AlN exhibits an absorption peak at 634 nm (1.96 eV). From first‐principles electronic structure calculations, the C‐doped AlN and carbon‐and‐oxygen‐doped AlN with a 1:1 ratio could be classified as p‐type, whereas the O‐doped AlN and 1:3 carbon‐and‐oxygen‐doped AlN were n‐type. One reason for the absorption peak at 634 nm may be a transition from the conduction band to an upper unoccupied state. These results suggest the possible control of optical and electronic properties of AlN via carbon‐and‐oxygen doping. [ABSTRACT FROM AUTHOR]

Highlights • InGaAsN/AlGaAs QWIPs for e-SWIR. • CBO values reaching up to ∼1 eV with GaAs technology. • Room temperature photocurrent response that spans between 1.1 and 2.2 μm. • Room temperature responsivity of 15 and 1 A/W for 1.65 μm and 2 μm, respectively. • Corresponding detectivity values of ∼1010 and ∼5 × 108 cm·Hz1/2/W at 1.65 μm and 2.0 μm, respectively. Potential detectivity values as high as ∼2 × 1012 and ∼1 × 1011 cm·Hz1/2/W for ∼1.65 μm and 2.0 μm, respectively can be achieved. Abstract We propose and demonstrate a novel concept to address high-performance, extended short wavelength (e-SWIR) photodetectors. Our approach is based on shifting the well-developed GaAs quantum-well infrared photodetector (QWIP) technology to e-SWIR wavelengths. In order to increase the available conduction band offsets (CBOs), we suggest incorporating nitrogen (N) atoms into the quantum well material. The incorporation of N atoms into III-Vs results in dilute-nitride highly mismatched alloys with lower bandgaps and higher CBOs. In our work, we demonstrate CBO values reaching up to ∼1 eV in InGaAsN/AlGaAs QWIPs. This large CBO makes these structures suitable for e-SWIR detection. The large CBO reduces the dark current dramatically and allows efficient detection at room temperature. In our study, we devised two similar InGaAsN/AlGaAs QWIP devices with twofold, 1% and 2% N composition. Based on the measured dark current data, we extracted activation energy barriers of 780 meV and 580 meV for the 1% and 2% N devices, respectively. The dark current and photocurrent spectral response behave in correlation to the change in the barriers' height. The photocurrent response of the 1% N device peaks at ∼2.25 μm and spans at a spectral range between 1.3 and 2.95 μm. The photocurrent response of the 2% N device is blue shifted to ∼1.42 μm and spans at a spectral range between 1.1 and 2.2 μm. The 2% N device exhibits lower dark currents and a strong photoresponse at room temperature, whereas the 1% N device exhibits a clear response only at temperatures below 150 K. The detection mechanism in the InGaAsN/AlGaAs QWIP devices is based on optical excitation of carriers from the quantum wells into highly-localized nitrogen-related E+ defect-like states located energetically above the conduction band edge. For this reason, the photoresponse is insensitive to the radiation polarization and exhibits low absorption efficiency on the order of 0.15% per quantum well. However, at the same time, the responsivity and photocurrent gain are very high due to the long lifetime of the highly localized excited states. The peak responsivity of the 2% N device is ∼70 A/W at room temperature. Significant responsivity is also available at the response tail at longer wavelengths, i.e., ∼15 and 1 A/W for 1.65 μm—the peak wavelength of the night glow emission and 2 μm—at the e-SWIR wavelengths, respectively. Corresponding detectivity values are ∼1010 and ∼5 × 108 cm·Hz1/2/W at 1.65 μm and 2.0 μm, respectively. These values are similar to those of other developing technologies. In-reach potential detectivity is estimated based on the measured data and can arrive easily to values as high as ∼2 × 1012 and ∼1 × 1011 cm·Hz1/2/W for ∼1.65 μm and 2.0 μm, respectively. The presented characteristics and potential performance indicate that InGaAsN/AlGaAs quantum wells are most suitable for efficient e-SWIR photodetection. [ABSTRACT FROM AUTHOR]

Highlights • Adding fertilizers had no adverse effects on the compost fermentation process. • Organic-inorganic aerobic co-composting increased compost nutrients contents. • Adding biochar contributed to the decomposition of stubborn carbonaceous matter. • Biochar improved nitrogen transformation and reduced nitrogen loss. • The 10–15% addition dose of biochar by weight is optimum in this study. Abstract In this article, the changes in carbon, nitrogen components, and humic substances during organic-inorganic aerobic co-composting, with adding biochar as an additive or not, were studied. Results showed that adding a certain amount of inorganic fertilizers had no adverse effects on the compost fermentation process. Biochar enhanced the temperature, pH, oxygen content in the compost piles and ultimately hastened the fermentation process. Biochar contributed to the decomposition of hemicellulose, cellulose, lignin and promoted compost humification. Adding biochar increased the contents of acid hydrolysis nitrogen, amino acid nitrogen, amino sugar nitrogen, unidentified organic nitrogen and decreased the content of ammonia organic nitrogen thus improved nitrogen transformation and reduced nitrogen loss. The addition of biochar increased the nutrients contents in mature composts. The amendment of 10–15% biochar by weight as an additive would be optimum for the co-composting of organic-inorganic materials. These results contributed to produce value-added composting fertilizers. [ABSTRACT FROM AUTHOR]

The structure of amorphous CNX thin films have a variety of chemical bond, and studies on these bonds ratios is very important because these ratios determine the appropriate technical use of these films. Therefore, this paper aim to investigate the relation between the conditions of preparation (deposition pressure) of a-CNx thin films prepared using PLD (Pulsed Laser Deposition) method and the film's structure. Results shown that the deposition pressure variation does not affecting the concentration in the same manner for all bonds in the film. Moreover, the sp2 cluster size and the order degree are related to the numerical value of the deposition pressure. [ABSTRACT FROM AUTHOR]

Straw incorporation is a useful management practice in sustainable agricultural systems to improve soil fertility and to reduce air pollution from straw burning. A three-year field experiment was conducted under two rice straw managements and four nitrogen (N) application rates in Rugao, China during 2010-2013, to examine whether straw management practices integrated with fertilizer N applications affect crop yield, N balance and N use efficiency in the wheat season of rice-wheat cropping systems. The results showed that straw incorporation had positive effects on plant N uptake and grain yield. This may be attributed to the greater soil water content and lower amount of seasonal rainfall. However, straw incorporation resulted in lower soil inorganic N and more N surplus at the early growth stage. Grain yield had a significant relation with wheat N uptake from sowing to jointing and from jointing to anthesis with straw incorporation. Therefore, our results suggest that in adjusting the ratio of basal and topdressing N fertilizer, it is important for the supply of optimum N to the crop and to maintain grain production with straw incorporation. [ABSTRACT FROM AUTHOR]

Abstract Precipitation hardened (PH) martensitic grade stainless steels are commonly used in additive manufacturing (AM) processes, but the heat treatment response can vary depending upon the powder feedstock composition. As-built AM 17–4 PH grade stainless steel fabricated using argon and nitrogen atomized feedstocks in separate powder bed fusion systems responded differently to standard heat treatment cycles. Materials fabricated from argon atomized feedstocks, containing low levels of nitrogen (0.01 wt%) and retained austenite (< 1%), responded as expected to standard solutionizing and aging heat treatment cycles. In contrast, materials fabricated from nitrogen atomized feedstocks, containing between 0.06 and 0.12 wt% nitrogen and up to 81% retained austenite, did not display peak aging with standard heat treatments and deviated from the expected overaging response with increasing aging temperatures. At the highest nitrogen and retained austenite levels, peak aging is found to occur at temperatures in excess of 680 °C, even though the material still contains retained austenite levels in the 20% range. These unexpected changes in the heat treat response are closely linked to differences in the nitrogen composition of the powder feedstock. Changes in the Ni and Cr equivalent values determined by other primary alloying elements also impact the heat treat response, even though the alloy compositions still fall within standard alloy element composition ranges. [ABSTRACT FROM AUTHOR]

Abstract This paper reports a study of 14N+ implanted Ti and Zr films analysed by Rutherford Backscattering Spectrometry (RBS). The fluences ranged from 4.0–10.0 × 1017 atoms·cm−2 and energies of 15–20 keV. Here, the nitrogen depth distributions were obtained simultaneously and independently for each RBS spectrum from the direct nitrogen signal and from the reduction of the backscattered yield from Ti and Zr (deficiency method). Fits to the RBS spectra show that the deficiency method clearly underestimates the 14N yield by 32% for Ti (and 45% for Zr) when compared to the direct nitrogen signal. This discrepancy reduces to 23% for Ti (and 43% for Zr) when the presence of nitrogen bubbles are simulated in the fits. Highlights • RBS deficiency method underestimates implanted nitrogen retention. • Nitrogen bubbles effects included in simulated RBS spectra. • Revision of stopping power cross sections required. [ABSTRACT FROM AUTHOR]

Highlights • Three models were applied to identify the main fouling mechanisms in a UF membrane. • Surface fouling had the best fits for the blocking laws and combined models. • In all cases similar fits were obtained with both models when N 2 bubbling was applied. • There are clear differences between filtration runs with and without gas bubbling. • The resistance-in-series model identified a post-cake fouling mechanism. Abstract Three models (blocking laws, combined and resistance-in-series) were applied to identify the prevailing fouling mechanisms in a submerged membrane in an up-flow anaerobic sludge blanket reactor treating municipal wastewater. Experimental runs were carried out at lab-scale with filtration periods of 4 and 10 min, followed by relaxation periods of one minute with and without nitrogen bubbling. In all conditions excepting one (IF4R), the blocking laws model showed a predominance of cake formation. With the combined model, cake formation coupled with intermediate, standard and complete fouling had the better fits in all conditions, excepting IF4 and IF4R. When sewage was fed, both models pointed at intermediate fouling in the absence of gas bubbling. The resistance-in-series model identified the positive effect of gas bubbling and a post-cake fouling behavior, not shown by the other two models. This modeling approach could be applied for achieving longer filtration runs in submerged UF membranes. [ABSTRACT FROM AUTHOR]

The theoretical and experimental vibrational studies for poly thiourea silver nitrate (2:1) complex using DFT method are performed on the basis of experimental data. During the geometry optimization process one equilibrium structure was found. The Mulliken charges, harmonic vibrational frequencies, Infrared and Raman intensities were calculated on the basis of quantum chemical density functional calculations using firefly (PC GAMESS) Version 7.1G. The clear – cut assignments of observed bands are performed on the basis of potential energy distribution (PED) analysis. Highest Occupied Molecular Orbital (HOMO) and the Lowest Occupied Molecular Orbital (LUMO) are obtained and graphically illustrated with minimum energy. The energy difference between HOMO and LUMO is analyzed. The other molecular properties like molecular electrostatic potential, Mulliken charges and thermodynamic properties of the title compound have also been calculated. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Ionic liquids (ILs) and poly(ionic liquid)s (PILs) are attracting significant research interest as safe and efficient electrolytes. Most research efforts focus on nitrogen based ILs and PILs (ammonium, imidazolium, pyridinium, etc.), while phosphorus based ILs and PILs have received relatively less attention despite exhibiting comparable ion conductivity over their nitrogen-based counterparts. In this review, we provide an overview of the structural elements in phosphorus based ILs and PILs that influence ion conductivity, such as ion size, ion polarizability, counterion selection, and backbone flexibility. We also highlight dominant physical parameters dictating ion conductivity including viscosity and glass transition temperature. A fundamental understanding of this structure-ion conductivity relationship will benefit the future rational design of phosphorus based ILs and PILs as electrolytes. [ABSTRACT FROM AUTHOR]

Nitrogen-rich cation 5-amino-1H-1,2,4-triazole-3-carbohydrazide and its derivatives were synthesized by a new molecular design strategy based on the energetic moiety combination. All derivatives were fully characterized by vibrational spectroscopy (IR), multinuclear (1H, 13C) NMR spectroscopy, elemental analysis, differential scanning calorimetry (DSC), and impact and friction-sensitivity tests. The structures of compounds 1-4, 7 and 8 were further confirmed by single-crystal X-ray diffraction and six different types of crystal packing were surprisingly discovered. The results show that the extensive hydrogen bonding interactions between the cations and anions lead to a complex 3D network, which contribute greatly to the high density, insensitivity and thermal stability of the 5-amino-1H-1,2,4-triazole-3-carbohydrazide salts. It is also found that the cationic form of 5-amino-1H-1,2,4-triazole-3-carbohydrazide can decrease the sensitivity and elevate the nitrogen content of the target salts effectively. Some of these salts exhibit reasonable physical properties, such as good thermal stability (up to 407 °C) and reasonable impact sensitivities (IS = 5-80 J). In addition, theoretical detonation properties of the energetic salts obtained with EXPLO 5 (version 6.02) confirm them as competitively energetic compounds comparable to those of RDX or HMX. [ABSTRACT FROM AUTHOR]

Salt marshes have the potential to intercept nitrogen that could otherwise impact coastal water quality. Salt marsh plants play a central role in nutrient interception by retaining N in above- and belowground tissues. We examine N uptake and allocation in two dominant salt marsh plants, short-form Spartina alterniflora and Distichlis spicata . Nitrogen uptake was measured using 15 N tracer experiments conducted over a four-week period, supplemented with stem-level growth rates, primary production, and microbial denitrification assays. By varying experiment duration, we identify the importance of a rarely-measured aspect of experimental design in 15 N tracer studies. Experiment duration had a greater impact on quantitative N uptake estimates than primary production or stem-level relative growth rates. Rapid initial scavenging of added 15 N caused apparent nitrogen uptake rates to decline by a factor of two as experiment duration increased from one week to one month, although each experiment shared the qualitative conclusion that Distichlis roots scavenged N approximately twice as rapidly as Spartina . We estimate total N uptake into above- and belowground tissues as 154 and 277 mg N·m −2 ·d −1 for Spartina and Distichlis , respectively. Driving this pattern were higher N content in Distichlis leaves and belowground tissue and strong differences in primary production; Spartina and Distichlis produced 8.8 and 14.7 g biomass·m −2 ·d −1 . Denitrification potentials were similar in sediment associated with both species, but the strong species-specific difference in N uptake suggests that Distichlis- dominated marshes are likely to intercept more N from coastal waters than are short-form Spartina marshes. The data and source code for this manuscript are available as an R package from https://github.com/troyhill/NitrogenUptake2016 . [ABSTRACT FROM AUTHOR]

Must nitrogen composition plays a key role on wine quality, affecting the development of alcoholic fermentation and the formation of volatile compounds. In order to provide additional information about the optimal time of harvest, we studied grape amino acid evolution pattern in relation to the accumulation of soluble solids along ripening. Additionally, we evaluate the amino acid profile of Grenache ( Vitis vinifera L.) grapevines. The results showed that the degree of berry maturity strongly influence the evolution patterns of all amino acids. Grenache behaved as an arginine accumulator variety. This amino acid was found to model the total amino acid concentration in Grenache musts. Generally, soluble solids maturity coincided with the nitrogen maturity at 25 ºBrix. Therefore, in Grenache grapevines, when amino acid composition is aimed to be maximized, the optimal grape harvest time, in terms of nitrogenous maturity, matches the timing at which berries reach their sugar maturity at 25 ºBrix. [ABSTRACT FROM AUTHOR]

Millimeter-sized nitrogen and sulfur co-doped microporous activated carbon spheres (NSCSs) were first synthesized from poly(styrene-vinylimidazole-divinylbenzene) resin spheres through concentrated H 2 SO 4 sulfonation, carbonization and KOH activation. Styrene (ST) and N-vinylimidazole (VIM) were carbon and nitrogen sources, while the sulfonic acid functional groups introduced by the simple concentrated sulfuric acid sulfonation worked simultaneously as cross-linking agent and sulfur source during the following thermal treatments. It was found that the surface chemistries, textural structures, and CO 2 adsorption performances of the NSCSs were significantly affected by the addition of VIM. The NSCS-4-700 sample with a molar ratio of ST: VIM = 1: 0.75 showed the best CO 2 uptake at different temperatures and pressures. An exhaustive adsorption evaluation indicated that CO 2 sorption at low pressures originated from the synergistic effect of surface chemistry and micropores below 8.04 Å, while at the moderate pressure of 8.0 bar, CO 2 uptake was dominated by the volume of micropores. The thermodynamics suggested the exothermic and orderly nature of the adsorption process, which was dominated by a physisorption mechanism. The high CO 2 adsorption capacity, fast kinetic adsorption rate, and great regeneration stability of the nitrogen and sulfur co-doped activated carbon spheres indicated that the as-prepared carbon adsorbents were good candidates for large-scale CO 2 capture. [ABSTRACT FROM AUTHOR]

Nitrogen is an essential, often limiting, factor in plant growth and development. To regulate growth under limited nitrogen supply, plants sense the internal and external nitrogen status, and coordinate various metabolic processes and developmental programs accordingly. This coordination requires the transmission of various signaling molecules that move across the entire plant. Cytokinins, phytohormones derived from adenine and synthesized in various parts of the plant, are considered major local and long-distance messengers. Cytokinin metabolism and signaling are closely associated with nitrogen availability. They are systemically transported via the vasculature from plant roots to shoots, and vice versa, thereby coordinating shoot and root development. Tight linkage exists between the nitrogen signaling network and cytokinins during diverse developmental and physiological processes. However, the cytokinin-nitrogen interactions and the communication systems involved in sensing rhizospheric nitrogen status and in regulating canopy development remain obscure. We review current knowledge on cytokinin biosynthesis, transport and signaling, nitrogen acquisition, metabolism and signaling, and their interactive roles in regulating root-shoot morphological and physiological characteristics. We also discuss the role of spatio-temporal regulation of cytokinins in enhancing beneficial crop traits of yield and nitrogen use efficiency. [ABSTRACT FROM AUTHOR]

A Pd catalyst supported on a composite containing nitrogen-doped carbon-modified titanium oxides (Pd/NC-Ti-O), and was prepared for formic acid electrooxidation. According to structure and morphology characterizations, NC-Ti-O consists of a nitrogen-doped carbon, TiO2, Ti2O3, and Ti2O, and the Pd/NC-Ti-O catalyst has a smaller particle size and more uniform dispersion as compared to the Pd/Ti4O7 catalyst. Electrochemical measurements displayed that the Pd/NC-Ti-O catalyst possesses a better electrocatalytic activity and stability towards the electrooxidation of formic acid than Pd/Ti4O7. The improvement of catalytic activity is mainly ascribed to the higher content of metallic Pd and stronger resistance to CO poisoning caused by NC-Ti-O. [ABSTRACT FROM AUTHOR]

Biofertilizers are considered as alternatives to chemical fertilizers for enhancing plant growth. However, only a few microorganisms responsible for nitrogen mineralization have been exploited. Furthermore, mineralization after biofertilizer application has not been well studied. In this paper, mineralization was assessed in soil samples inoculated or not with the ammonifier Bacillus amyloliquefaciens DT over a five-week incubation period. The results showed that ammonifying bacteria amendment increased CO 2 and N 2 O emission, as well as inorganic nitrogen and total soluble nitrogen concentrations. Importantly, after inoculation, the net nitrogen mineralization rate increased by 23.23% and 32.16% in the unfertilized control and pig manure with chemical fertilizer soil samples, respectively. High-throughput sequencing of internal transcribed spacer sequences and16S rRNA showed that ammonifier amendment changed the composition of the microbial community. Notably, members of the bacterial phyla Firmicutes and Actinobacteria and genera Lysobacter and Sphingopyxis were enriched, while those belonging to the fungal phylum Ascomycota were depleted after B. amyloliquefaciens DT inoculation, verifying that this ammonifier DT contributed to disease suppression in terms of community structure. Thus, it is concluded that B. amyloliquefaciens DT can serve as a potential biofertilizer for promoting plant growth owing to its abilities of mineralization and disease suppression. [ABSTRACT FROM AUTHOR]

New experimental and computational data on apokamps produced by repetitive discharges in air, including a detailed description of the research techniques used, are presented. It has been shown that plasma bullets–streamers in apokamps at low frequencies could start not only from the bright offshoot but also directly from the discharge channel. The experimental and computational data demonstrate that the visual color of apokamp changes from blue to red as the intensity ratio of the second to the first positive nitrogen system decreases with the decreasing pressure. [ABSTRACT FROM AUTHOR]

This review is meant to provide an overview of the electrochemical biosensors based on Nitrogen doped graphene quantum dots (N-GQDs) for analytical approaches, along with significant advances over the last several years in related technologies. In addition, this review described: i ) Most frequently applied principles in biosensing based on of N-GQDs ii ) The aspects of fabrication in the perspective of biosensing applications iii ) The potential of various electrochemical, biosensors for the determination of target analytes within sub-micromolar range and the circumvention of the most serious problem in biosensing will be discussed. iv ) Some of multiplex electrochemical biosensors have been discussed with and without labels. v ) We also summarize the latest developments in the applications of biosensors methods for detection of important analytes in real samples. vi ) The development trends of biosensors are also introduced, including newly developed integrated biosensors based on (N-GQDs). [ABSTRACT FROM AUTHOR]

We investigated the metamizole metabolite 4-formylaminoantipyrine (4-FAA) by 1 H dynamic nuclear magnetic resonance. 4-FAA exhibits a carbon-nitrogen partial double bond that rotates slowly enough, on a resonance time scale, to provide the simultaneous spectra of two rotamers. We examined various solvents in an attempt to understand how protic and aprotic environments influence the anti and syn rotamer equilibriums. Moreover, we compared experimental data and theoretical calculations to evaluate the thermodynamic parameters of the rotational process. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel HNAD bacteria, Acinetobacter oleivorans AHP123, was isolated. • Strain AHP123 can effectively remove ammonia nitrogen at 45 °C. • The ammonia nitrogen of 95.92 mg/L could remove 97.93% in 24 h by the strain. • Strain AHP123 may have incomplete HNAD and nitrogen assimilation pathways. • Nitrogen assimilation is the main nitrogen removal path of strain AHP123. A novel aerobic strain of Acinetobacter oleivorans AHP123 was isolated from activated sludge, which could conduct heterotrophic nitrification and denitrification simultaneously. This strain has excellent NH 4 +-N removal ability, with 97.93% removal rate at 24-hour. To identify the metabolic pathways of this novel strain, genes of gam , glnA , gdhA , gltB , nirB , nasA , nar , nor , glnK and amt were detected by genome analysis. Through RT-qPCR, it was found that the expression of key genes confirmed two possible ways of nitrogen removal in strain AHP123: nitrogen assimilation and heterotrophic nitrification aerobic denitrification (HNAD). However, the absence of some common HNAD genes (amo , nap and nos) suggested that strain AHP123 might have a different HNAD pathway from other HNAD bacteria. Nitrogen balance analysis revealed that strain AHP123 assimilated most of the external nitrogen sources into intracellular nitrogen. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nitrification-denitrification existed in AD systems and contributed to TAN removal. • Biogas circulation and AC addition lowered the TAN by 6% and 2%, respectively. • Both strategies enriched nitrification-/denitrification-related bacteria or genes. • Their combination had a synergetic effect on enrichment of specific bacteria/genes. • Combined strategy led to a 24% lower TAN level and a 44% higher CH 4 yield. This study investigated the biological nitrogen removal mechanisms during the anaerobic digestion of swine manure and the effects of biogas circulation and activated carbon (AC) addition. Biogas circulation, AC addition, and their combination increased the methane yield by 25.9%, 22.3%, and 44.1%, respectively, when compared to the control. Nitrogen species analysis and metagenomic results indicated that nitrification–denitrification was the dominant ammonia removal pathway in all digesters with little oxygen, while anammox did not occur. Biogas circulation could promote mass transfer and induce air infiltration to enrich nitrification- and denitrification-related bacteria and functional genes. And AC might act as an electron shuttle to facilitate ammonia removal. The combined strategies showed a synergetic effect on the enrichment of nitrification and denitrification bacteria and functional genes, significantly lowering the total ammonia nitrogen by 23.6%. A single digester with biogas circulation and AC addition could enhance methanogenesis and ammonia removal via nitrification and denitrification. [ABSTRACT FROM AUTHOR]

Using stable isotope analysis of nitrogen, for the first time the hypothesis on different sources of inorganic nutrients for two groups of littoral algae in Lake Baikal was confirmed. Strongly attached filamentous algae of genus Ulothrix, which developed in the wave-braking zone at depth 0.5 m, and loosely attached filamentous algae of genus Spirogyra, which developed in deeper layers 3.0–5.0 m in a low-turbulence zone, get inorganic nutrients presumably from surface discharge and groundwater inputs, respectively. Besides, stoichiometric ratios C:N and N:P in biomass of the algae indicated that growth of Spirogyra in Lake Baikal was likely limited by nitrogen, while growth of Ulothrix was limited by phosphorus. [ABSTRACT FROM AUTHOR]

The ordered structure of the guest-free microporous metal-organic framework zinc 5-tert-butyl isophthalate {Zn[(CH3)3CC6H3(CO2)2]} has been determined and shown to be easily loaded with methanol to form {Zn[(CH3)3CC6H3(CO2)2]}·CH3OH. The methanol forms a S6-symmetric hexamer within the pores of the material that is uniquely defined by the void space and exerts a subtle structural effect on the framework structure of the host. The work demonstrates the use of this type of metal-organic framework as a matrix to isolate unique molecular clusters in a facile manner. [ABSTRACT FROM AUTHOR]

The reactions of {Cr6} horseshoe chains {[nPr2NH2]3[Cr6F11(O2CtBu)10]}2, 1 and precursors of actinides and group IV metals led to a series of ring complexes [nPr2NH2][Cr7TiF6O2(O2CtBu)16], 2, [nPr2NH2][Cr6Ti2F5O3(O2CtBu)16], 3, [Cr6ThF7(O2CtBu)15 (Me2SO)], 4, [(nPr2NH2)2(Cr6Th2F12(O2CtBu)16)], 5 and [nPr2NH2][Cr6U2O2F8(O2CtBu)16(Me2SO)], 6. X-ray structure studies indicate that the {Cr6} chains maintain their structures in these complexes, acting as polydentate fluoride ligands. Their static magnetic properties were measured and fitted by isotropic exchange Hamiltonian. In accordance with 1, the magnetic exchanges between CrIII are antiferromagnetic, while the exchange interactions can be modified by the tetravalent metals. For compound 6, ferromagnetic exchanges JCr–U and JU–U are obtained. EPR spectra of compounds 2–5 were measured at Q band and were simulated. The spectrum of 2 has the same profile as {Cr7Cd} and {Cr7Zn} rings with a ground state S = 3/2. 3, 4 and 5 give similar EPR spectra with S = 0 ground states. [ABSTRACT FROM AUTHOR]

The present review lists the papers and patents dealing with the class of polycondensed heterocycles called benzopyrroloxazines published in the last decades. The survey is limited to substances characterized by the presence of a bridgehead N atom, which means that the present N atom serves to connect different rings within the same molecule. In the case of benzopyrroloxazines, the bridgehead N atom belongs at the same time to the pyrrole and oxazine rings. All other compounds not possessing this feature were kept out accordingly. Relevant synthetic methods to such compounds have been outlined. Many different biological properties have been attributed to several functionalized derivatives of these heterocycles and cited within the review. [ABSTRACT FROM AUTHOR]

A pressurizer is a major component used to control a system pressure in a primary coolant system of a pressurized water reactor. To identify the system pressure characteristics on nitrogen gas-water and steam-water pressurizers for an integral pressurizer water reactor, an experimental study is carried out on the integral test facility, VISTA-ITL, which is a scaled down facility of the SMART plant. According to the experimental results, the pressurization rate and peak pressure are affected by the pressurizer type. The pressurization and depressurization rate with the steam pressurizer is smaller than the gas pressurizer since water has its inherent characteristic having latent heat while a nitrogen has ideal gas properties. The safety valve in both the gas and steam pressurizers is not opened during the transient. It is one of the characteristics of the integral reactor SMART design with a large pressurizer volume. The cooldown rate of the primary coolant system during the later part transient depends on the decay heat level regardless of the pressurizer type. [ABSTRACT FROM AUTHOR]

Decomposing vertebrate cadavers release large, localized inputs of nutrients. These temporally limited resource patches affect nutrient cycling and soil organisms. The impact of decomposing cadavers on soil chemistry is relevant to soil biology, as a natural disturbance, and forensic science, to estimate the postmortem interval. However, cadaver impacts on soils are rarely studied, making it difficult to identify common patterns. We investigated the effects of decomposing pig cadavers (Sus scrofa domesticus) on soil chemistry (pH, ammonium, nitrate, nitrogen, phosphorous, potassium and carbon) over a one-year period in a spruce-dominant forest. Four treatments were applied, each with five replicates: two treatments including pig cadavers (placed on the ground and hung one metre above ground) and two controls (bare soil and bags filled with soil placed on the ground i.e. "fake pig" treatment). In the first two months (15-59 days after the start of the experiment), cadavers caused significant increases of ammonium, nitrogen, phosphorous and potassium (p<0.05) whereas nitrate significantly increased towards the end of the study (263-367 days; p<0.05). Soil pH increased significantly at first and then decreased significantly at the end of the experiment. After one year, some markers returned to basal levels (i.e. not significantly different from control plots), whereas others were still significantly different. Based on these response patterns and in comparison with previous studies, we define three categories of chemical markers that may have the potential to date the time since death: early peak markers (EPM), late peak markers (LPM) and late decrease markers (LDM). The marker categories will enhance our understanding of soil processes and can be highly useful when changes in soil chemistry are related to changes in the composition of soil organism communities. For actual casework further studies and more data are necessary to refine the marker categories along a more precise timeline and to develop a method that can be used in court. [ABSTRACT FROM AUTHOR]

Gas-phase 14 N and 15 N NMR studies of nitrogen and synthetic air pressurized up to 300 bar were performed. It was found that the magnetic shielding of an isolated N 2 molecule, σ 0 (N) = −63.4(2) ppm, is in good agreement with the results of ab initio calculations. The binary N 2 -O 2 interactions contribute to shielding an order of the magnitude larger than the N 2 -N 2 pairs. For nitrogen the three body collisions become observable by NMR for pressure higher than 200 bar and the appropriate coefficient can be practically assigned to the interaction between one molecule of N 2 and a pair of O 2 molecules. [ABSTRACT FROM AUTHOR]

This paper presents the results of the investigation of pollutant build-up on impervious surfaces of a parking lot in Belgrade, Serbia during the summer months. Contaminant build-up was found to be greater on asphalt surfaces directly exposed to vehicular traffic than on concrete walkways. The difference in the amounts of accumulated pollutants between asphalt and concrete were significant: for total solids (TS), total suspended solids (TSS), chemical oxygen demand (COD), heavy metals and total phosphorus (TP) accumulations were two to three times higher, while only 30% higher for total nitrogen (TN) and anions. Build-up of most of the measured parameters was best described by power functions. The highest surface loads were found for solids, COD, iron and zinc. A strong correlation was found between turbidity, TS, TSS, COD, heavy metals and phosphorus, while conductivity, nitrates and nitrites were weakly correlated to other parameters. [ABSTRACT FROM AUTHOR]

Nitrogen and phosphorus co-doped carbon hollow spheres (NPCHSs) have been prepared by a carbonization and subsequent chemical activation route using dehydrated polypyrrole hollow spheres as the precursor and KOH as the activating agent. NPCHSs are interconnected into a unique 3D porous network, which endows the as-prepared carbon to exhibit a large specific surface area of 1155 m 2  g −1 and a high specific capacitance of 232 F g −1 at a current density of 1 A g −1 . The as-obtained NPCHSs present a high-level heteroatom doping with N, O and P contents of 11.4, 6.7 and 3.5 wt%, respectively. The capacitance of NPCHSs has been retained at 89.1% after 5000 charge–discharge cycles at a relatively high current density of 5 A g −1 . Such excellent performance suggests that NPCHSs are attractive electrode candidates for electrical double layer capacitors. [ABSTRACT FROM AUTHOR]

Background/Aims: As a model organism for a pleiomorphic marine planktonic primary producer, Phaeodactylum tricornutum has been studied on a molecular level under diverse cultural conditions. But little is known about its morphological, nutritional or transcriptomic responses under grazing stress. Methods: To assess microalgal molecular and cellular responses to grazer presence, we conducted transcriptome profiling in combination with growth rate, biovolume, fatty acid content, carbon and nitrogen content measurements in the model diatom Phaeodactylum tricornutum. RNA-sequencing was used to evaluate the transcriptomic response to grazing stress for P. tricornutum strain CCAP 1055/1. Results: Among the differentially expressed genes, we found down-regulation of genes involved in pathogen resistance, and in fatty acid biosynthesis pathways, while mitosis-involved genes were up-regulated. Experimentally testing morphological and biochemical responses in five strains of the species, we detected strain-specific significant effects of simulated grazing pressure in altered growth rates, biovolume and nutritional composition. Conclusion: Our research reveals the associated molecular and cellular responses to grazing effects in P. tricornutum and extends the understanding of co-evolutionary roles in regulating grazing defence between P. tricornutum and its grazer. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we examined the impact of temperature on the carbon and nitrogen trophic transfers from a macroalga to a macro‐grazer by the use of dual 13C‐ and 15N‐labeling. Using an experimental approach in mesocosms, individuals of the urchin Psammechinus miliaris were maintained for 1 month at 17°C (mean summer temperature in the Bay of Brest) and at 20°C (maximum summer temperature) and fed with 13C‐ and 15N‐labeled Solieria chordalis. The results showed that the urchins’ 13C uptake was 0.30 µg13C g dry weight (DW)−1 at 17°C and 0.14 µg13C g DW−1 at 20°C at the end of the experiment. The lower uptake at the higher temperature may be attributed to a decrease in metabolic activity at 20°C, involving lower feeding and/or respiration rates. Conversely, no significant effect of temperature was detected on 15N uptake. At the end of the experiment, the urchins’ 15N uptake was 0.04 µg15N g DW−1 at 17°C and 0.03 µg15N g DW−1 at 20°C. This suggests that temperature may affect carbon and nitrogen trophic fluxes differently. The use of dual isotope labeling offers interesting prospects and needs to be further extended in order to better understand trophic interactions in marine communities and the consequences of current environmental changes, such as global warming. [ABSTRACT FROM AUTHOR]

Abstract: Background and Aims: The concentration and composition of nitrogen (N) in must is critical to yeast fermentation and aroma profiles in wine. We investigated the effect of adding branched‐chain amino acids (BCAAs, including l‐valine, l‐leucine and l‐isoleucine) to a non‐limited N medium on the formation of aromatic compounds and on gene expression patterns of the wine yeast Saccharomyces cerevisiae. Methods and Results: A synthetic N‐sufficient must was supplemented with BCAAs and fermented with S. cerevisiae. The fermentation kinetics, aroma characteristics and yeast global gene expression in wine with addition of BCAAs were compared with that of the Control. Addition of BCAAs improved yeast growth and fermentation activity, increased the production of higher alcohols, medium‐chain fatty acids and their corresponding esters (82, 34 and 49% increment compared to that of the Control, respectively). The comparative transcriptomic analysis revealed that 25 genes varied in their expression during fermentation with added BCAAs relative to that of the Control, which are mainly involved in yeast growth and proliferation (GIP1, DIT2, RCK1, SPO1 and MEK1) and transport of amino acids (GAP1). Conclusions: An increase in BCAA transport ability and in yeast population is the main reason for achieving an increased concentration of volatile aroma compounds in wine with addition of BCAAs. Significance of the Study: Our results suggest that adding BCAAs into N‐sufficient must is still an efficient way to adjust wine's aromatic composition and improve aroma complexity. [ABSTRACT FROM AUTHOR]

Aerobic rice is a promising rice production system which enables rice to grow in water-constrained environments and provides an alternative to continuous flooding irrigation. Although significant water savings are reported in aerobic systems in different lowland regions, a negative impact in crop performance prevents its wide deployment. The main reasons for grain yield decreases are given to be genotype and inappropriate water supply. However, agronomic practices such nitrogen management can interfere in overall crop performance of rice due to the influence of soil moisture on N availability to crop uptake. The goal of this research was to establish a relationship between nitrogen use and crop performance by comparing flooding conditions to aerobic rice in a tropical environmental with adequate water supply. A field experiment was carried out from 2014 to 2016 with an experimental design of split plot with irrigation regime (IR) in the main plot: continuous flooding (CF) and non-flooding aerobic (NF), and in the subplot fertilizer nitrogen rates: (0, 50, 150 and 250 kg ha −1 ). Crop above ground biomass (AGB) and nitrogen uptake (NU) were quantified during crop development only in the 0 and 150 kg ha −1 subplots, as was the relationship between AGB, NU, grain yield and its components and all nitrogen rates at harvest. The aerobic rice provided higher NU throughout rice development. At harvesting, NU and panicle density (PD) had different relationships to N rates among CF and NF, with NF showing 18% higher NU and 27% PD across years and N rate. The grain yield (GY) relationship to N rates was also distinct in 2014 and 2015, and GY across N rates in NF was 20% and 12% higher than CF for 2014 and 2015, respectively. We conclude that lowland rice managed through aerobic system improves nitrogen uptake by rice crop as long the water filled space remains around 60%. [ABSTRACT FROM AUTHOR]

The recent trends in microalgal cultures are focused on the biorefinery of the biomass components. Some of them are not completely valorised, for example starch. Since there is a wide market for starch products in food and non-food industries, the exploitation of microalgal starch fractions could improve the economic sustainability of microalgae production. In this perspective, the optimization of nitrogen and carbon source uptake for starch accumulation is a critical point for reducing the nitrogen requirement footprint and to increase CO 2 capture. In this study, four robust microalgal strains, already known as starch-accumulating strain, were investigated: Chlorella sorokiniana , Scenedesmus vacuolatus , Dunaliella tertiolecta , and Tetraselmis chuii. C. sorokiniana was selected as the best starch producer in the biorefinery context, and the role nitrogen and CO 2 concentration had on the starch production was investigated. For light irradiance of 300 μmol m −2 s −1 the optimal nitrogen concentration for growth and starch accumulation resulted 32 mg L −1 . The CO 2 concentration clearly does not influence the starch accumulation, but concentrations distant from 2% negatively influence microalgal growth, affecting the final starch productivity. The biomass composition during the batch growth of C. sorokiniana was also analysed in order to explicitly characterise the dynamic of starch accumulation during the different growth phases. Protein content decreased during N-depletion, carbohydrates were mainly produced during the early N-depletion, followed by the accumulation of lipids in the late depletion. [ABSTRACT FROM AUTHOR]

Pursuit of low-cost and large-scale method to prepare carbon quantum dots (CQDs) is a persistent objective in recent years. In this work, we have successfully synthesized a series of nitrogen-doped carbon quantum dots (N-CQDs) under different hydrothermal temperature employing Eichhornia crassipes (ECs) as precursors. Considering the pollution ability to water and low-cost, this study may direct the novel path to convert waste material to useful quantum dots. After measurements such as TEM, XRD, Raman, XPS, PL as well as the UV–vis absorbance ability, outstanding optical properties have been discovered. In this fashion, solar cells are tentative to be fabricated, yielding the maximized solar-to-electrical conversion efficiency of 0.17% with a good fill factor of 67%. Meanwhile, the above-mentioned quantum dots also show the up-conversion ability, suggesting the potential application in infrared detection or broadening light-absorbing devices. [ABSTRACT FROM AUTHOR]

Abstract: Despite fast development of hybrid perovskite solar cells, there are many fundamental questions related to the perovskite film which remain open. For example, there are contradicting theoretical reports on the role of the organic methylammonium cation (CH3NH3+) in the methylammonium lead triiodide (CH3NH3PbI3) perovskite film. From one side it is reported that the organic cation does not contribute to electronic structure of the CH3NH3PbI3 film. From the other side, valence band maximum fluctuations, dependent on the CH3NH3+ rotation, have been theoretically predicted. The resonant X‐ray photoelectron spectroscopy results reported here show experimental evidence of nitrogen contribution to the CH3NH3PbI3 electronic structure. Moreover, the observed strong resonances of nitrogen with the I 5s and the Pb 5d‐6s levels indicate that the CH3NH3PbI3 valence band is extended up to ≈18 eV below the Fermi energy, and therefore one should also consider these shallow core levels while modeling its electronic structure. [ABSTRACT FROM AUTHOR]