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• A novel SNW-1 incorporated chiral polymer monolith was developed. • The cellulase@(GMA-EDMA-SNW-1) monolith exhibited excellent chiral selectivity. • SNW-1 incorporation improved resolution and column efficiency. • The repeatability and stability of the prepared monolith are satisfactory. A covalent organic framework, Schiff base network-1 (SNW-1), was synthesized and incorporated into cellulase based poly(glycidyl methacrylate-co-ethylene dimethacrylate) (cellulase@poly(GMA-EDMA-SNW-1)) monolith to afford a novel chiral stationary phase for capillary electrochromatography (CEC). SNW-1 is attractive as a stationary phase for CEC because it not only features high surface areas but also provides conjugate structures and abundant amine groups to give π-π electrostatic stacking and hydrogen bonding property. Incorporation of SNW-1 into monolithic column could improve the column efficiency and increase the interactions between the tested racemates and the stationary phase thus significantly improved their CEC separation. The obtained monoliths were characterized by scanning electron microscopy, elemental analysis and nitrogen adsorption. Moreover, effects of SNW-1 concentration, immobilization pH of cellulase and CEC conditions were also investigated. Under the optimized conditions, the cellulase@poly(GMA-EDMA-SNW-1) monolith exhibited excellent enantioseparation performance for eight pairs of different classes of chiral drugs including β-blockers, antihistamines and anticoagulants. Satisfactory repeatability was achieved with relative standard deviations for intra-day, inter-day and column-to-column runs less than 4.5%, and batch-to-batch runs less than 6.8%. The experiment results reveal that the combination of the versatile features of monoliths and unique properties of SNW-1 could be a promising strategy for chiral separation. [ABSTRACT FROM AUTHOR]

Coordination polymers of 2′,3′,5′,6′-tetramethyl-[1,1′:4′,1′′-terphenyl]-4,4′′-dicarboxylic acid with Cu(II), Co(II) and Cd(II) have been synthesized and characterized by IR spectroscopy, single crystal X-ray diffraction, thermogravimetric analysis and nitrogen sorption studies. Three new 3D-metal–organic frameworks based on 2′,3′,5′,6′-tetramethyl-[1,1′:4′,1′′-terphenyl]-4,4′′-dicarboxylic acid (H 2 L) and Co, Cu, and Cd nodes have been synthesized. The complexes were characterized by elemental, thermogravimetric analysis, IR spectroscopy, single crystal, powder X-ray diffraction and gas sorption experiments. The crystal structure of [Cu 2 L 2 (H 2 O) 2 ] n (1) corresponds to a two-dimensional coordination polymer, in which the metal nodes are two crystallographically equivalent Cu(II) atoms linked by four μ 2 -O,O′ carboxylate ligands in a centrosymmetric {Cu 2 O 10 } paddle-wheel building block. The structure of compound [CoL(dmso)] n (2) has a 3D metal–organic coordination lattice, in which the metal centers are connected by the linear organic ligand to generate a dense three-dimensional coordination polymer. Also, a three-dimensional coordination network was identified in the case of compound [Cd 2 L 2 (dmf)] n (3), whose structure is very similar to that of compound 2. In compound 3 , the carboxylate groups of the linear L2− spacers behave as μ 2 - κ3O, O′:O tridentate bridging ligands. The compounds have a high thermal stability. Polymers 3 and 1 have moderate porosity (specific surface areas of approximately 900 m2/g and 600 m2/g, respectively), while polymer 2 has a dense structure. [ABSTRACT FROM AUTHOR]

Deepwater wells have the basic conditions for the generation of trapped annular pressure caused by thermal expansion. Nitrogen is eligible medium to mitigate annular pressure for its high compressibility. Therefore, this paper studies the action mechanism, effect evaluation and applicability analysis of the mitigation by injecting nitrogen. To this end, an equation is established to calculate the annular pressure when nitrogen exists in annulus according to PVT property and volume relationship. And then a method is proposed to solve the equation based on volume segmentation and wellbore radial thermal resistance distribution. The casing strength is checked by safety efficient to verify the mitigation effect. The results indicate that nitrogen mitigates trapped annular pressure mainly by volume compensation. The mitigation is strong and effective. Considering mitigation effect and cost-effectiveness, the optimal injection volume should be between 5% and 15%. The nitrogen is suitable for mitigation of in deep/ultra-deep water wells although the increase of water depth undermines the mitigation effect. The mitigation is still effective even the annular liquid is of high expansibility and low compressibility when adequate nitrogen is injected. Strong mitigation effect can be obtained in high temperature reservoir and wells of high production rate. In conclusion, nitrogen has good applicability and strong effect in the mitigation of trapped annular pressure. • Nitrogen mitigates annular pressure by volume compensation. • A model built to calculate annular temperature and pressure. • Mitigation is strong and effective. • Nitrogen has good applicability to mitigate annular pressure. [ABSTRACT FROM AUTHOR]

Aluminum black dross (ABD) is a solid waste of aluminum smelting process that causes serious environmental and public health problems. In addition, it imposes significant disposal costs to the aluminum industry. In this study, synthesis and characterization of mesoporous alumina (MA) from the ABD using a novel recycling procedure consisting of leaching at low temperature (85 °C) and atmospheric pressure, co-precipitation, separation through selective dissolution, re-precipitation, aging and finally calcination at 600 °C for 2 h. No hard or soft template was used during the formation of the gel. The as-synthesized MA had a specific surface area, total pore volume and average pore diameter of 123–162 m2/g, 0.37 cm3/g and 10.6 nm, respectively which were obtained by nitrogen sorption analysis. The as-synthesized MA possessed more than 98% purity. Its XRD pattern exhibited the characteristic peaks of gamma, eta, theta, and delta phase alumina. FESEM and TEM analyses revealed nanoscale morphology of the as-synthesized MA; having crystal size of ∼11 nm. The TGA analysis showed that the as-synthesized MA is thermally stable and exhibits only ∼5 wt% mass loss for heating from 30 to 800 °C. The characterization of solid residue at the end of the proposed process proved that it contains mainly silica phase which can alternatively be reused as filling agent or aggregate in concrete materials applications. It is quite clear that the process of production of MA from the ABD is feasible and practical and provides a novel mitigation to the environmental problems of the ABD. • This work studies template-free synthesis of mesoporous alumina from Al black dross. • The as-synthesized mesoporous alumina had a specific surface area of 123–162 m2/g. • The specific pore volume of the as-synthesized mesoporous alumina was 0.37 cm3/g. • The as-synthesized mesoporous alumina possessed more than 98% purity. [ABSTRACT FROM AUTHOR]

Abstract Synthesis and adsorption studies of the SBA-15 immobilizing perylene and pyrene dyes are described in this work. The functionalization is carried out with amine groups through post-synthesis using amino-propyl triethoxysilane (APTES) and ethanol or toluene as solvent. The resulting functionalized material is investigated as a matrix for the immobilization of perylene-3,4,9,10-tetracarboxylic dianhydride (PDA). Further exploration of the immobilization of 1-Pyrenecarboxaldehyde (PCA) is detailed. The obtained materials were characterized by FTIR and fluorescence spectroscopy, nitrogen adsorption analysis and X-ray diffraction (XRD). The textural characterization of the functionalized samples shows the decrement of the average pore sizes and the surface area as consequence of the APTES and fluorescent dyes immobilization. Compared with the pristine SBA-15, the solids obtained by functionalization with PDA yielded red-coloured samples, which show absorption bands at λ = 670 nm in solid state and λ = 570 nm in solution. The PDA dye is bonded to the SBA-15 network and it shows absorption or emissions properties for the new hybrid solids. The fluorescence of these species are preserved if the PDA molecules remains with a more flexible structure. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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]

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]

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]

Plant-Nitrogen is a vital element that significantly influences plant growth, fruit quality, and yield. However, excessive Nitrogen (N) fertilizer application can have adverse effects on both plant health and environment. Traditional methods of plant-N analysis face numerous challenges like time-consuming procedures, hazardous chemicals, low precision, and limited throughput, hindering efficient and accurate analysis in laboratories. In recent years, Near-Infrared Spectroscopy (NIRS) has emerged as an innovative and rapid method for plant-N analysis, offering non-destructive, cost-effective, and real-time measurements with high accuracy and throughput. This research aimed to explore the potential of utilizing miniaturized handheld Near-Infrared (NIR) sensors in conjunction with machine learning (ML) and chemometrics to assess the N status of tomato plants leaves in the field. Through this study, A comprehensive analysis involving 18 models utilizing different regression and spectral preprocessing methods was conducted. The findings indicate that combining the first- or second-order SG derivatives with the MSC is the optimal spectral data preprocessing method, and that incorporating wavelengths selection techniques, such as GA-PLS and GA-SVM, improves the predictive accuracy of the models by reducing the number of wavelengths considered. The best model's performance was assessed using R2, RMSE, and RPD, yielding values of 81.0–82.8, 7.4–7.8, and 2.3–2.4, respectively. Overall, this study demonstrates that combining NIRS with ML and chemometrics enables effective evaluation of plant-N status using leaves total N content as a proxy variable and emphasizes the significance of integrating spectral preprocessing, modeling, and wavelengths selection techniques to enhance data quality and mitigate the influence of environmental factors that may impact the accuracy of NIRS-based evaluations. • Rapid and efficient method for assessing plant nutritional status was introduced. • Machine learning and chemometrics have unleashed the power of NIR spectroscopy in the analysis of nutrients in fresh leaves. • Leaf diagnosis was a good proxy for evaluating plants nutritional status. • Leaf tissue analysis offered crucial information about the plant status. • Meta-Modeling made it possible to develop powerful calibrations. [ABSTRACT FROM AUTHOR]

To solve the nitrate accumulation phenomenon in recirculating aquaculture system (RAS). This study aimed to provide a sufficient organic carbon source, denitrifying bacteria, and a suitable microenvironment for denitrification in RAS. Denitrifying capsules were prepared using the encapsulation method, the morphology, microbial community and influencing factors for nitrogen removal efficiency of the denitrifying capsules in synthetic RAS wastewater were investigated. The denitrifying capsules had a porous, rough, and loose structure, with a diameter of approximately 6 mm and a density of approximately 1.05 g per cubic centimeter. The effect of a low ratio of solid-to-liquid (10:1) and temperature (15 °C) on nitrate removal was significant during the initial acclimation period (1-10d). After the enclosed denitrifying bacteria activity was recovered, the influence was not significant. At the end of the test, the nitrate removal rate could reach more than 80% even at a lower ratio of solid-to-liquid (10:1) or at 15 °C. The capsule exhibited a short adaptation time for diverse types of substrates and adapted well to the substrate concentration. Under low influent nitrate or nitrite loading, the removal rate reached 80% on the 6th day, which was earlier than with high influent nitrate loading. The denitrification rate experiment showed that the nitrate removal rate could reach 80.14% at 14 h and finally stabilize at approximately 81.89%. The capsule-supported denitrification process was a zero-order reaction and the denitrification rate of the capsule was calculated to be 109.0 mg N/L-capsule·h. The longtime evaluation indicated that until the semen litchi powder was exhausted, the capsule could retain a high nitrate removal rate. Functional enzyme analysis reveals the nitrogen conversion pathway in the capsule included denitrification, dissimilatory nitrate reduction and nitrogenfixation. The porous structure and good adaptability to environmental conditions of the denitrifying capsule would help to achieve denitrification and reduce the nitrate content on the present RAS, without increasing infrastructure investment. • Core-shell structure denitrifying capsule was designed for denitrification in RAS. • The capsule adapted well to substrate concentrations and temperature. • Afther a short activation time the nitrate removal rate could reach 96.6%. • Denitrification prosess in RAS may achieve easily with the denitrifying capsule. [ABSTRACT FROM AUTHOR]

Aerobic denitrification is a feasible and sustainable process for nitrogen removal in environmental protection. The C/N ratio was the vital one that has a significant impact on the performance. However, comprehension of the C/N ratio effect on this bioprocess was not well clarified. In this study, the response of an aerobic denitrifier (Pseudomonas balearica strain RAD-17) to the C/N ratio was investigated from a view of metabolism. It was found that a high total nitrogen (TN) removal efficiency of about 95% was achieved with the dosing C/N ratio of 7.5, while only a slight increase when the dosing C/N ratios were further increased to a high range of 10–30. The carbon validity was out of sync with TN removal and a balance between the two was realizable at a dosing C/N ratio of 7.5 based on the economic consideration. Moreover, weakened assimilation while enhanced respiration along with the increased C/N ratios was revealed, evidenced by the decreased net intracellular nitrogen and increased nitrogenous gas proportions in nitrogen balance analysis. The growth characteristics in terms of cell number and OD 600 showed a division for the high flux of nitrate and organics directed to assimilation and respiration, respectively. The expression levels of carbon and nitrate metabolism-related function genes in P. balearica supported the results above. The C/N ratio of 5.0–7.5 was supposed to be the turning region for the metabolism division between assimilation and respiration in aerobic denitrifying. The results are expected to offer a guideline for the decision made for organics supply for the aerobic denitrification process and support its sustainable application. [Display omitted] • C/N ratio of 7.5 was the threshold value to achieve TN removal of over 95%. • The carbon validity and nitrogen removal efficiency had an inverse relationship. • Nitrogen balance and growth property of P. balearica showed a metabolic division. • Expression levels of nitrate and carbon related functional genes were investigated. • Turning region of C/N ratio for microbial assimilation and respiration was 5.0–7.5. [ABSTRACT FROM AUTHOR]

• An indoor artificial wind-driven rain experiment was performed. • The relationships between soil erosion, nitrogen loss and wind velocity on windward slopes were established. • The soil erosion and nitrogen loss processes under wind-driven rain were attempted to simulate by improved KINEROS2. Wind-driven rain (WDR) is a common source of soil erosion in nature and usually occurs on windward slopes. This study investigated the effects of WDR events at different wind velocities of 0, 2, 3, 5, 7, 8 m s−1 and rainfall intensities of 30, 60, 90 mm h−1 on runoff, sediment yield, and total nitrogen (TN) loss processes on windward slopes. Additionally, the study constructed quantitative relationships between TN loss rate and simultaneous runoff and sediment using indoor simulated WDR experiments. The distributed soil erosion model KINEROS2 was then modified to embedded with these relationships, and used to simulate and verify the runoff, sediment yield, and TN loss processes during WDR events on windward slopes. The results showed an initial substantial increase followed by a gradual stabilization trend in runoff rates, sediment yield loss rates, and sediment-associated TN loss rates on windward slopes. As wind velocity increased from 0 to 8 m s−1 under a rainfall intensity of 90 mm h−1, the average runoff rate, sediment yield rate, and sediment-associated TN loss rate decreased linearly by 4.30%–16.13%, 9.82%–34.44%, and 14.54–46.42%, respectively. However, runoff-associated TN loss rate increased in a linear trend of 26.49%–137.59%. Similar trends were observed at rainfall intensities of 30 and 60 mm h−1. When simulated using the KINEROS2 and nitrogen migration model embedded with mathematical relationships between wind velocity and soil erosion and TN loss on windward slopes, the NSE and R2 of runoff, sediment, and TN loss processes were 0.49–0.83 and 0.59–0.89, 0.21–0.82 and 0.42–0.88, and 0.21–0.73 and 0.38–0.83, respectively. This study provides insights into the effects of WDR events on TN loss at plot scale and offers guidance for KINEROS2 application under WDR conditions at different slope directions and watershed scales. [ABSTRACT FROM AUTHOR]

• Thermal degradation kinetics of biodegradable polymer blends was evaluated • Kissinger-Akahira-Sunose and Vyazovkin isoconversional methods were applied • The composition and morphology of the blends influenced their thermal behavior • The addition of nanochitin diminished the effective activation energy of the blends • Avrami-Erofeev function was the most probable kinetic mechanism of the systems studied In this article, the influence of blend ratio of plasticized poly(lactic acid)/poly(3-hydroxybutyrate) (PLA/PHB) and chitin nanoparticles (ChNP) nanocomposites on the thermal stability and degradation kinetics has been investigated using thermogravimetric analysis under nitrogen atmosphere at four different heating rates (i.e., 5, 15, 30, and 50°C/min). The derivative thermogravimetric curves have indicated single-step and two-step degradation processes for individual polymers and polymer blends, respectively. It suggests immiscibility or partial miscibility between the polymers. The degradation kinetic parameters were studied over the 30 – 500°C temperature range by using the Kissinger-Akahira-Sunose (KAS) and Vyazovkin isoconversional methods under non-isothermal conditions. The average values of the effective activation energies of the deconvoluted PHB and PLA peaks in the PLA:PHB 70:30 (B73) blends were higher than those of the pure polymers, while in the PLA:PHB 60:40 (B64) blends were lower, which was attributed to the different morphology of the blends. Furthermore, the effective activation energy of the nanocomposites diminished due to the catalyzing effect of the chitin nanoparticles. By means of the invariant kinetic parameters (IKP) method, it was possible to evaluate the preexponential factor and the activation energy of the blends without any assumptions concerning kinetic model. The invariant activation energies calculated were in accordance with the ones estimated by the isoconversional methods. Finally, Avrami-Erofeev function was determined as the most probable kinetic mechanism of the systems studied by applying the Sestak-Berggren equation. [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]

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]

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]

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]

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]

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]

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]

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]

The elements of zirconium and nitrogen were used as doping elements and the sol-gel method was applied for the preparation of nanoparticles of TiO 2 , TiO 2 /Zr 0.1 , TiO 2 /N 0.1 and TiO 2 /Zr 0.05 ,N 0.05 . Then, the photocatalytic activity of nanoparticles of undoped and doped TiO 2 was studied in the treatment of wastewater samples containing 2,4-dinitrotoluene (2,4-DNT), 2,6- dinitrotoluene (2,6-DNT) and trinitrotoluene (TNT) under the visible light irradiation. During radiation time of 12 h, a treatment efficiency of 35.9, 42.4, 61.5 and 67.2% was obtained in the presence of the photocatalysts of TiO 2 , TiO 2 /Zr 0.1 , TiO 2 /N 0.1 and TiO 2 /Zr 0.05 ,N 0.05 , respectively. As it is seen, the co-doped titanium dioxide shows the highest photocatalytic activity in the visible region compared to the other used photocatalysts. The nanoparticles of TiO 2 /Zr 0.05 ,N 0.05 were characterized by field emission – scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), B.E.T. surface analysis and diffuse reflectance spectroscopy (DRS). The XRD patterns did not show any change in the crystalline structure of doped TiO 2 . The DRS spectra indicated the band-gap energies of 3.17, 2.98, 2.91 and 2.78 eV for TiO 2 , TiO 2 /Zr 0.1 , TiO 2 /N 0.1 and TiO 2 /Zr 0.05 ,N 0.05 nanoparticles, respectively. [ABSTRACT FROM AUTHOR]

Lignite is well known for its hard-to-float property. Many surfactants, including anionic, cationic and non-ionic have been applied to improve the floatation efficiency. In this work, cationic dodecylamine was applied to pretreat the lignite samples with different densities, which are −1.45 g/cm 3 , 1.45–1.80 g/cm 3 and +1.80 g/cm 3 . The surface charged properties of the raw samples were determined by a zeta potential analyzer. The adsorption performance was characterized by XPS and UV/VIS spectrophotometer methods. From the surface zeta-potential results, three curves of zeta-potential figures versus pH value are similar to each other qualitatively in the pH range 5–8, which indicates that the organic structure has the similar ionization/ protonation ability with inorganic minerals at neutral pH. The negatively charged surfaces attract the cationic dodecylamine molecules at neutral pH for the three density fractions, which is shown by the XPS narrow sweep of heteroatom nitrogen before and after the pretreatment process. On the lignite surface, nitrogen was mainly existed in two forms of pyrrolic and quaternary. After the pretreatment, the quaternary-N peak was increased on the lignite surface due to the adsorption of dodecylamine molecules, especially on the surface of the highest density fraction. Correspondingly, UV/VIS spectrophotometer results showed that the adsorption amounts of dodecylamine molecules were 11.4, 18.7 and 20.0 mg/g on the surface of the samples from low to high density. On the other hand, the flotation result showed that more high ash particles and some low ash ones were both floated with the increase of dodecylamine dosage. Hence, if dodecylamine is to be used in lignite flotation, reagents should be added to selectively depress the adsorption process of cationic dodecylamine on the low or high ash particles. [ABSTRACT FROM AUTHOR]

A facile and one-step strategy has been developed for the preparation of highly fluorescent nitrogen and phosphor co-doped carbon quantum dots (NP-CQDs) through the thermal treatment of the mixture of citric acid and O -phosphorylethanolamine. The as-prepared NP-CQDs emit strong blue-green light under irradiation of 365 nm light and show emission maxima at 475 nm in aqueous solution. And these NP-CQDs exhibit great stability in high-salt conditions, excellent photostability and a high quantum yield of about 8.45%. Interestingly, the NP-CQDs have been successfully utilized for the sensitive and selective fluorometric detection of Fe 3+ without interference from other ions in aqueous solution. Moreover, we have found that the NP-CQDs can enhance the photocatalytic activity of TiO 2 for the degradation of dyes under simulated sunlight irradiation. [ABSTRACT FROM AUTHOR]

We report a facile strategy to prepare nitrogen functionalized reduced graphene oxide (NRGO) by using ammonia plasma treatment of reduced graphene oxide (RGO) synthesized via a chemical method. The chemical composition of NRGO and its morphology was studied extensively by various surface probing techniques such as Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and Raman spectroscopy. Electrochemical investigations were performed using various redox probes such as potassium ferricyanide and hexaammineruthenium (III) chloride indicated a large electroactive surface area of NRGO and fast electron transfer. Meanwhile the direct electron transfer of hemoglobin (Hb) immobilized on NRGO was confirmed by a reduction peak that appeared on the cyclic voltammogram. Further, the electron transfer coefficient (α) and heterogeneous electron transfer rate constant (ks) for Hb at the NRGO were calculated to be 0.43 and 1.05 s −1 respectively. Moreover, the GCE/NRGO/Hb modified electrode was employed for the determination of nitrite over the linear range from 5 to 300 nM with a limit of detection of 1.3 nM. Our results suggest that NRGO is a potential candidate for the electrochemical sensing of nitrite. [ABSTRACT FROM AUTHOR]

The application of nitrogen (N) and herbicides are commonly used to fertilize crops and protect them against weed development, but are also considered as soil and environment pollutants. Even so, the individual and combined non-target effects of N fertilizers and herbicides on multitrophic interactions within agrosystems are not well known. From soil samples collected in the field, we examined the effects of the direct application of glyphosate and/or N fertilization on microbial activities and soil nutrient status. In addition, we investigated the increase in biomass and, nutrient acquisition of the bean ( Phaseolus vulgaris ) and the consequences of the applications of N and glyphosate on the performance of the herbivore aphid ( Aphis fabae ). From soils that did (N +) or did not receive (N0) synthetic N fertilization over a 6-year period, we assessed the effects of glyphosate (CK, without glyphosate; FR, field rate of glyphosate) and N fertilization (N +, with N fertilization; N0, without N fertilization) applications in a mesocosm experiment for 75-days. Following the 75 day treatment, the biological and physiological consequences, both belowground and aboveground were determined. The growth of arbuscular mycorrhizal fungi (AMF) and dehydrogenase activity, were negatively affected following N + fertilization and the application of the FR of glyphosate, while in the absence of glyphosate, alkaline phosphatase (AIP) activity was reduced. Functional microbial responses were unaffected by both N and glyphosate, even when applied in combination. Conversely, the N fertilization significantly increased the nitrate content (NO 3 − ) in the CK soils and the total N in the FR soils, compared to CK/N0 and FR/N0 soils. The combined effects of glyphosate and nitrogen fertilization (FR/N +) significantly decreased the soil C:N ratio, but significantly increased nitrification compared to CK/N0 and FR/N0 soils. The FR/N + treatments positively affected plant performance, improving the total chlorophyll, sucrose, ammonium, amino acid content, and pod biomass, compared to the CK/N0 and FR/N0 soils. Unlike glyphosate, which did not appear to exert an effect when applied alone or in combination, N fertilization significantly increased aphid nymph survival. The non-metric multidimensional scale allowed us to establish belowground and aboveground interactions with glyphosate and N fertilization. We conclude that glyphosate and N fertilization have negative effects on soil microflora and potential pests, but do not necessarily affect belowground and aboveground interactions, and may offer equal or superior benefits to crop productivity. [ABSTRACT FROM AUTHOR]

Background: Nutritional management of preterm infants aims to approximate the tissue growth and body composition of a fetus of the same postmenstrual age. The adequacy of the quality of protein supply can influence the rate and the relative quality of weight gain. Objective:We investigated the protein balance according to feeding regimen and the association between human milk feeding and fatfree mass content at the term-corrected age in very-low-birth-weight preterm infants. Design: A prospective observational study was conducted. Inclusion criteria were as follows: healthy infants, gestational age =32 wk, birth weight <1500 g, stable clinical conditions, and feeding by mouth with human milk or formula at discharge. Infants were enrolled at hospital discharge. At enrollment, macronutrient intakes and protein balance were determined. Anthropometric measurements and body composition were also assessed. The nutritional composition of human milk was calculated by infrared spectroscopy. The protein balance was determined according to the nitrogen balance standard method. Body composition was assessed by an air-displacement plethysmography system. At the term-corrected age, anthropometry and body composition assessments were repeated. Results: Seventeen preterm infants fed fortified human milk and 15 preterm infants fed formula were enrolled. At discharge, despite similar macronutrient intakes, infants fed fortified human milk showed a higher nitrogen balance (expressed as mg · kg-1 · d-1) compared with preterm formula-fed infants (mean ± SD: 488.3 ± 75 compared with 409.8 ± 85 mg · kg-1 · d-1, P = 0.009). At termcorrected age, growth was similar in the 2 groups, whereas fortified human milk-fed infants showed a higher percentage of fat-free mass (85.1% ± 2.8% compared with 80.8% ± 3.2%, P = 0.002). Moreover, at multiple linear regression, fat-free mass content was independently associated with being fed human milk (R² = 0.93, P < 0.0001). Conclusion: Our findings suggest that human milk feeding is associated with early fat-free mass deposition in healthy and stable preterm infants. [ABSTRACT FROM AUTHOR]

Shortage of non-renewable energies, increase in fossil fuel prices and stricter emissions regulations due to high NOx and soot emissions emitted from combustion of heavy diesel fuels by compression ignition engines, has led consumers to use renewable, cleaner and cheap fuels. An investigation has been computationally carried out to explore the influences of hydrogen and nitrogen addition on engine performance such as indicated power and indicated specific energy consumption and amounts of pollutant emissions like NOx, soot, and CO in an HSDI (High-Speed Direct Injection) diesel engine. Optimized sub-models, such as turbulence model, spray model, combustion model and emissions models have selected for the main CFD code. Meanwhile, HF (Homogeneity Factor) has been employed for analysing in-cylinder air-fuel mixing quality under various addition conditions. After validations with experimental data of diesel combustion with a single addition of 4% hydrogen and combined addition of 6% hydrogen + 6% nitrogen, investigations have conducted for modeling mixing and combustion processes with additions of hydrogen and nitrogen by ranges of 2–8% (v/v). Results showed that a single addition of H 2 increased NOx and decreased CO and soot and improved ISEC and IP. In the case of nitrogen addition, NOx decreased, both CO and soot emission increased and ISEC and IP considerably ruined compared with NDC operation. Based on the results obtained for simultaneous addition of N 2 (8% of v/v) and H 2 (8% of v/v), NOx and soot emissions decreased by 11.5% and 42.5% respectively, and ISEC and IP improved 25.7% and 13%, respectively. But amount of CO emissions had an increase of 52% should be paid necessary attention as a main disadvantage. [ABSTRACT FROM AUTHOR]

Precipitation behavior and tensile properties have been investigated for 15Cr-15Mn-4Ni austenitic steels containing 0.2 wt% carbon and/or 0.2 wt% nitrogen. During aging at 600–1000 °C, precipitates such as σ, M 23 C 6 , and Cr 2 N were formed and time-temperature-precipitation diagrams were constructed. The type, size, and density of precipitates depended on the carbon and nitrogen contents. The nitrogen addition suppressed carbide formation while the effect of carbon addition on nitride precipitation was comparatively small. The evolution of tensile properties after aging is explained by the changes in solid solution strengthening and deformation modes caused by the precipitation. The precipitation of M 23 C 6 slightly decreased yield strength and elongation while it increased ultimate tensile strength. On the other hand, the precipitation of Cr 2 N hardly affected tensile properties due to its low volume fraction. [ABSTRACT FROM AUTHOR]

Herbivory can trigger physiological processes resulting in leaf and whole plant functional changes. The effects of chronic infestation by an insect on leaf traits related to carbon and nitrogen economy in three Prunus avium cultivars were assessed. Leaves from non-infested trees (control) and damaged leaves from infested trees were selected. The insect larvae produce skeletonization of the leaves leaving relatively intact the vein network of the eaten leaves and the abaxial epidermal tissue. At the leaf level, nitrogen content per mass ( N mass ) and per area ( N area ), net photosynthesis per mass ( A mass ) and per area ( A area ), photosynthetic nitrogen-use efficiency ( PNUE ), leaf mass per area ( LMA ) and total leaf phenols content were measured in the three cultivars. All cultivars responded to herbivory in a similar fashion. The N mass , A mass , and PNUE decreased, while LMA and total content of phenols increased in partially damaged leaves. Increases in herbivore pressure resulted in lower leaf size and total leaf area per plant across cultivars. Despite this, stem cumulative growth tended to increase in infected plants suggesting a change in the patterns of biomass allocation and in resources sequestration elicited by herbivory. A larger N investment in defenses instead of photosynthetic structures may explain the lower PNUE and A mass observed in damaged leaves. Some physiological changes due to herbivory partially compensate for the cost of leaf removal buffering the carbon economy at the whole plant level. [ABSTRACT FROM AUTHOR]

Herein, the multiporous MnO/N-doped carbon (MnO/NC) composite based on the abundant and inexpensive electrolytic manganese dioxide were fabricated through a facile microwave-assisted carbonthermal reduction, combined with a subsequent in-situ polymerization of polydopamine onto MnO along with thermal treatment. As an anode material, it retains a reversible capacity of 770.5 mAh g −1 at 300 mA g −1 and high Coulombic efficiency of 99% over 500 cycles, superior than those values of the pure multiporous MnO alone. The impressive performance is attributed to the splendid structure stability contributed by well-connected three-dimensional porous configuration and the enhanced reaction kinetics as well as electrical conductivity incurred by N-doped carbon layer with multiple type nitrogen. [ABSTRACT FROM AUTHOR]

A dual-reflux pressure swing adsorption (DR-PSA) process using LiLSX zeolite to produce both high purity and recovery of N 2 and O 2 from mimical air (21%O 2 /79%N 2 ) was developed in the commercial software, Aspen Adsorption. In this work, adsorption equilibrium isotherms of pure oxygen and nitrogen on LiLSX zeolite were firstly measured and fitted with the extended Langmuir model in order to describe the behavior of the static adsorption. A total of sixteen experiments were carried out on a laboratory scale DR-PSA apparatus for verifying the reliability of the mathematical model. Finally, an optimal operating condition was obtained by comparing the purity and recovery of products under different experimental conditions. Results revealed that feed or light reflux time (t FE/LR ), heavy reflux flow rate (Q HR ), vacuum pressure (P L ) and feed flow rate (Q F ) all had significant effects on the process performance. O 2 in light product could be enriched to 99.1% with recovery of 98.0% while N 2 in heavy product is 99.0% in concentration with recovery of 99.3% under the optimal experimental condition. All in all, the DR-PSA process could be capable of producing both heavy and light products simultaneously with high purity and recovery. [ABSTRACT FROM AUTHOR]

Nitrogen plays a key role in the fermentation and secondary metabolites formation. The aim was to study the influence of vine nitrogen applications on grape amino acid composition. Nitrogen sources applied to Tempranillo and Monastrell grapevines were phenylalanine and urea, during two seasons. Results showed that the application of these compounds had little effect on grape amino acid composition, regardless of variety and vintage. This could be due to the fact that vineyards did not present nitrogenous requirements. Thus, variety was the determining factor in Asp, Glu, Gln, Cit, Met, Gly, Gaba, Val, Ile, and Leu while season was the factor that most affected Thr, Arg, Ala, and Lys due its implication on berry ripening. The concentration of the remaining amino acids was influenced by two or three of the factors studied. Therefore, when the vineyard has adequate nitrogen nutritional status, grape amino acid content was determined by variety and vintage. [ABSTRACT FROM AUTHOR]

Aquaponics is a promising technology combining aquaculture with hydroponics. In this study, algal-bacterial consortia were introduced into aquaponics, i.e., algal-bacterial based aquaponics (AA), to improve the nitrogen utilization efficiency (NUE) of aquaponics. The results showed that the NUE of AA was 13.79% higher than that of media-based aquaponics (MA). In addition, higher NO 3 − removal by microalgae assimilation led to better water quality in AA, which made up for the deficiencies of poor aquaponic management of nitrate. As a result of lower NO 3 − concentrations and dramatically higher dissolved oxygen (DO) concentrations caused by microalgae photosynthesis in the photobioreactor, the N 2 O emission of AA was 89.89% lower than that of MA, although nosZ gene abundance in MA’s hydroponic bed was approximately 30 times over that in AA. Considering the factors mentioned above, AA would improve the sustainability of aquaponics and have a good application foreground. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the feasibility of near infrared (NIR) transmittance spectroscopy to predict cheese ripeness using the ratio of water-soluble nitrogen (WSN) to total nitrogen (TN) as an index of cheese maturity (WSN/TN). Fifty-two Protected Designation of Origin cow milk cheeses of 5 varieties (Asiago, Grana Padano, Montasio, Parmigiano Reggiano, and Piave) and different ripening times were available for laboratory and chemometric analyses. Reference measures of WSN and TN were matched with cheese spectral information obtained from ground samples by a NIR instrument that operated in transmittance mode for wavelengths from 850 to 1,050 nm. Prediction equations for WSN and TN were developed using (1) cross-validation on the whole data set and (2) external validation on a subset of the entire data. The WSN/TN was calculated as ratio of predicted WSN to predicted TN in cross-validation. The coefficients of determination for WSN and TN were >0.85 both in cross- and external validation. The high accuracy of the prediction equations for WSN and TN could facilitate implementation of NIR transmittance spectroscopy in the dairy industry to objectively, rapidly, and accurately monitor the ripeness of cheese through WSN/TN. [ABSTRACT FROM AUTHOR]